Publications of P. Bork
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2024 7 publication(s).
707.
Efficient Recovery of Complete Gut Viral Genomes by Combined Short- and Long-Read Sequencing.
2024 Apr 19; 11(13): e2305818. PubMed: 38240578.
Abstract + PDFCurrent metagenome assembled human gut phage catalogs contained mostly fragmented genomes. Here, comprehensive gut virome detection procedure is developed involving virus-like particle (VLP) enrichment from ≈500 g feces and combined sequencing of short- and long-read. Applied to 135 samples, a Chinese Gut Virome Catalog (CHGV) is assembled consisting of 21,499 non-redundant viral operational taxonomic units (vOTUs) that are significantly longer than those obtained by short-read sequencing and contained ≈35% (7675) complete genomes, which is ≈nine times more than those in the Gut Virome Database (GVD, ≈4%, 1,443). Interestingly, the majority (≈60%, 13,356) of the CHGV vOTUs are obtained by either long-read or hybrid assemblies, with little overlap with those assembled from only the short-read data. With this dataset, vast diversity of the gut virome is elucidated, including the identification of 32% (6,962) novel vOTUs compare to public gut virome databases, dozens of phages that are more prevalent than the crAssphages and/or Gubaphages, and several viral clades that are more diverse than the two. Finally, the functional capacities are also characterized of the CHGV encoded proteins and constructed a viral-host interaction network to facilitate future research and applications.
706.
Interactive Tree of Life (iTOL) v6: recent updates to the phylogenetic tree display and annotation tool.
Letunic I, Bork P
2024 Apr 13; [Epub ahead of print] PubMed: 38613393.
AbstractThe Interactive Tree Of Life (https://itol.embl.de) is an online tool for the management, display, annotation and manipulation of phylogenetic and other trees. It is freely available and open to everyone. iTOL version 6 introduces a modernized and completely rewritten user interface, together with numerous new features. A new dataset type has been introduced (colored/labeled ranges), greatly upgrading the functionality of the previous simple colored range annotation function. Additional annotation options have been implemented for several existing dataset types. Dataset template files now support simple assignment of annotations to multiple tree nodes through substring matching, including full regular expression support. Node metadata handling has been greatly extended with novel display and exporting options, and it can now be edited interactively or bulk updated through annotation files. Tree labels can be displayed using multiple simultaneous font styles, with precise positioning, sizing and styling of each individual label part. Various bulk label editing functions have been implemented, simplifying large scale changes of all tree node labels. iTOL's automatic taxonomy assignment functions now support trees based on the Genome Taxonomy Database (GTDB), in addition to the NCBI taxonomy. The functionality of the optional user account pages has been expanded, simplifying the management, navigation and sharing of projects and trees. iTOL currently handles more than one and a half million trees from >130 000 individual user accounts.
705.
Terlipressin therapy is associated with increased risk of colonisation with multidrug-resistant bacteria in patients with decompensated cirrhosis.
Mücke MM, Hernández-Tejero M, Gu W, Kuhn M, Janz M, Keller MI, Fullam A, Altepeter L, Mücke VT, Finkelmeier F, Schwarzkopf KM, Cremonese C, Hunyady PM, Heilani MW, Uschner FE, Schierwagen R, Brol MJ, Fischer J, Klein S, Peiffer KH, Hogardt M, Shoaie S, Coenraad MJ, Bojunga J, Arroyo V, Zeuzem S, Kempf VAJ, Welsch C, Laleman W, Bork P, Fernandez J, Trebicka J, MICROB-PREDICT and PREDICT Study Group of the EASL-CLIF Consortium
2024 Apr 27; 59(7): 877-888. PubMed: 38414095.
AbstractPatients with cirrhosis are susceptible to develop bacterial infections that trigger acute decompensation (AD) and acute-on-chronic liver failure (ACLF). Infections with multidrug-resistant organisms (MDRO) are associated with deleterious outcome. MDRO colonisation frequently proceeds MDRO infections and antibiotic therapy has been associated with MDRO colonisation.
704.
High-throughput anaerobic screening for identifying compounds acting against gut bacteria in monocultures or communities.
Müller P, de la Cuesta-Zuluaga J, Kuhn M, Baghai Arassi M, Treis T, Blasche S, Zimmermann M, Bork P, Patil KR, Typas A, Garcia-Santamarina S, Maier L
2024 Mar 13; 19(3): 668-699. PubMed: 38092943.
AbstractThe human gut microbiome is a key contributor to health, and its perturbations are linked to many diseases. Small-molecule xenobiotics such as drugs, chemical pollutants and food additives can alter the microbiota composition and are now recognized as one of the main factors underlying microbiome diversity. Mapping the effects of such compounds on the gut microbiome is challenging because of the complexity of the community, anaerobic growth requirements of individual species and the large number of interactions that need to be quantitatively assessed. High-throughput screening setups offer a promising solution for probing the direct inhibitory effects of hundreds of xenobiotics on tens of anaerobic gut bacteria. When automated, such assays enable the cost-effective investigation of a wide range of compound-microbe combinations. We have developed an experimental setup and protocol that enables testing of up to 5,000 compounds on a target gut species under strict anaerobic conditions within 5 d. In addition, with minor modifications to the protocol, drug effects can be tested on microbial communities either assembled from isolates or obtained from stool samples. Experience in working in an anaerobic chamber, especially in performing delicate work with thick chamber gloves, is required for implementing this protocol. We anticipate that this protocol will accelerate the study of interactions between small molecules and the gut microbiome and provide a deeper understanding of this microbial ecosystem, which is intimately intertwined with human health.
703.
Functional and evolutionary significance of unknown genes from uncultivated taxa.
Rodríguez Del Río Á, Giner-Lamia J, Cantalapiedra CP, Botas J, Deng Z, Hernández-Plaza A, Munar-Palmer M, Santamaría-Hernando S, Rodríguez-Herva JJ, Ruscheweyh HJ, Paoli L, Schmidt TSB, Sunagawa S, Bork P, López-Solanilla E, Coelho LP, Huerta-Cepas J
AbstractMany of Earth's microbes remain uncultured and under-studied, limiting our understanding of the functional and evolutionary aspects of their genetic material, which remain largely overlooked in most metagenomic studies. Here, we analyzed 149,842 environmental genomes from multiple habitats and compiled a curated catalog of 404,085 functionally and evolutionarily significant novel (FESNov) gene families exclusive to uncultivated prokaryotic taxa. All FESNov families span multiple species, exhibit strong signals of purifying selection, and qualify as new orthologous groups, thus nearly tripling the number of bacterial and archaeal gene families described to date. The FESNov catalog is enriched in clade-specific traits, including 1,034 novel families that can distinguish entire uncultivated phyla, classes, and orders, likely representing synapomorphies that facilitated their evolutionary divergence. Using genomic context analysis and structural alignments, we predicted functional associations for 32.4% of FESNov families, including 4,349 high-confidence associations with important biological processes. These predictions provide a valuable hypothesis-driven framework, which we employed to experimentally validate a new gene family involved in cell motility and a novel set of antimicrobial peptides. We also demonstrate that the relative abundance profiles of novel families can discriminate between environments and clinical conditions, leading to the discovery of potentially new biomarkers associated with colorectal cancer. We expect this work to enhance future metagenomics studies and expand our knowledge of the genetic repertory of uncultivated organisms.
702.
SPIRE: a Searchable, Planetary-scale mIcrobiome REsource.
Schmidt TSB, Fullam A, Ferretti P, Orakov A, Maistrenko OM, Ruscheweyh HJ, Letunic I, Duan Y, Van Rossum T, Sunagawa S, Mende DR, Finn RD, Kuhn M, Pedro Coelho L, Bork P
2024 Jan 5; 52: D777-D783. PubMed: 37897342.
Abstract + PDFMeta'omic data on microbial diversity and function accrue exponentially in public repositories, but derived information is often siloed according to data type, study or sampled microbial environment. Here we present SPIRE, a Searchable Planetary-scale mIcrobiome REsource that integrates various consistently processed metagenome-derived microbial data modalities across habitats, geography and phylogeny. SPIRE encompasses 99 146 metagenomic samples from 739 studies covering a wide array of microbial environments and augmented with manually-curated contextual data. Across a total metagenomic assembly of 16 Tbp, SPIRE comprises 35 billion predicted protein sequences and 1.16 million newly constructed metagenome-assembled genomes (MAGs) of medium or high quality. Beyond mapping to the high-quality genome reference provided by proGenomes3 (http://progenomes.embl.de), these novel MAGs form 92 134 novel species-level clusters, the majority of which are unclassified at species level using current tools. SPIRE enables taxonomic profiling of these species clusters via an updated, custom mOTUs database (https://motu-tool.org/) and includes several layers of functional annotation, as well as crosslinks to several (micro-)biological databases. The resource is accessible, searchable and browsable via http://spire.embl.de.
701.
Review: Opportunities and barriers for omics-based biomarker discovery in steatotic liver diseases.
Thiele M, Villesen IF, Niu L, Johansen S, Sulek K, Nishijima S, Van Espen L, Keller M, Israelsen M, Suvitaival T, de Zawadzki A, Juel HB, Brol MJ, Stinson SE, Huang Y, Alvarez Silva MC, Kuhn M, Anastasiadou E, Leeming DJ, Karsdal M, Matthijnssens J, Arumugam M, Dalgaard LT, Legido-Quigley C, Mann M, Trebicka J, Bork P, Jensen LJ, Hansen T, Krag A, MicrobLiver and GALAXY consortia
AbstractThe rising prevalence of liver diseases related to obesity and excessive use of alcohol is fuelling an increasing demand for accurate biomarkers aimed at community screening, diagnosis of steatohepatitis and significant fibrosis, monitoring, prognosis and prediction of treatment efficacy. Breakthroughs in omics methodologies and the power of bioinformatics have created an excellent opportunity to combine clinical needs with technological advancements. Omics technologies allow for advanced investigations into biological processes from the genes to transcription and regulation, to circulating protein, metabolite and lipid levels, as well as the microbiome including bacteria, viruses and fungi. We consequently find ourselves in a period of rapid progress in technology and bioinformatics that may allow for development of precision biomarkers for personalised medicine. However, there are important barriers to consider in omics biomarker discovery and validation, including the use of semi-quantitative measurements from untargeted platforms, which may exhibit high analytical, inter- and intra-individual variance. Standardising methods and the need to validate across diverse populations, presents a challenge, partly due to disease complexity and the dynamic nature of biomarker expression in different disease stages. Lack of validity causes lost opportunities when studies fail to provide the knowledge needed for regulatory approvals, all of which contributes to a delayed translation of these discoveries into clinical practice. While no omics-based biomarkers have matured to clinical implementation, the extent of data generated through omics-technologies holds the power of hypothesis-free discovery of a plethora of candidate biomarkers to be further validated. To explore the many opportunities of omics technologies, hepatologists need detailed knowledge of commonalities and differences between the various omics layers, and both the barriers to and advantages of these approaches.
2023 12 publication(s).
700.
Evidence of a causal and modifiable relationship between kidney function and circulating trimethylamine N-oxide.
Andrikopoulos P, Aron-Wisnewsky J, Chakaroun R, Myridakis A, Forslund SK, Nielsen T, Adriouch S, Holmes B, Chilloux J, Vieira-Silva S, Falony G, Salem JE, Andreelli F, Belda E, Kieswich J, Chechi K, Puig-Castellvi F, Chevalier M, Le Chatelier E, Olanipekun MT, Hoyles L, Alves R, Helft G, Isnard R, Køber L, Coelho LP, Rouault C, Gauguier D, Gøtze JP, Prifti E, Froguel P, MetaCardis Consortium , Zucker JD, Bäckhed F, Vestergaard H, Hansen T, Oppert JM, Blüher M, Nielsen J, Raes J, Bork P, Yaqoob MM, Stumvoll M, Pedersen O, Ehrlich SD, Clément K, Dumas ME
2023 Sep 20; 14(1): 5843. PubMed: 37730687.
Abstract + PDFThe host-microbiota co-metabolite trimethylamine N-oxide (TMAO) is linked to increased cardiovascular risk but how its circulating levels are regulated remains unclear. We applied "explainable" machine learning, univariate, multivariate and mediation analyses of fasting plasma TMAO concentration and a multitude of phenotypes in 1,741 adult Europeans of the MetaCardis study. Here we show that next to age, kidney function is the primary variable predicting circulating TMAO, with microbiota composition and diet playing minor, albeit significant, roles. Mediation analysis suggests a causal relationship between TMAO and kidney function that we corroborate in preclinical models where TMAO exposure increases kidney scarring. Consistent with our findings, patients receiving glucose-lowering drugs with reno-protective properties have significantly lower circulating TMAO when compared to propensity-score matched control individuals. Our analyses uncover a bidirectional relationship between kidney function and TMAO that can potentially be modified by reno-protective anti-diabetic drugs and suggest a clinically actionable intervention for decreasing TMAO-associated excess cardiovascular risk.
699.
proGenomes3: approaching one million accurately and consistently annotated high-quality prokaryotic genomes.
Fullam A, Letunic I, Schmidt TSB, Ducarmon QR, Karcher N, Khedkar S, Kuhn M, Larralde M, Maistrenko OM, Malfertheiner L, Milanese A, Rodrigues JFM, Sanchis-López C, Schudoma C, Szklarczyk D, Sunagawa S, Zeller G, Huerta-Cepas J, von Mering C, Bork P, Mende DR
2023 Jan 6; 51: D760-D766. PubMed: 36408900.
Abstract + PDFThe interpretation of genomic, transcriptomic and other microbial 'omics data is highly dependent on the availability of well-annotated genomes. As the number of publicly available microbial genomes continues to increase exponentially, the need for quality control and consistent annotation is becoming critical. We present proGenomes3, a database of 907 388 high-quality genomes containing 4 billion genes that passed stringent criteria and have been consistently annotated using multiple functional and taxonomic databases including mobile genetic elements and biosynthetic gene clusters. proGenomes3 encompasses 41 171 species-level clusters, defined based on universal single copy marker genes, for which pan-genomes and contextual habitat annotations are provided. The database is available at http://progenomes.embl.de/.
698.
eggNOG 6.0: enabling comparative genomics across 12 535 organisms.
Hernández-Plaza A, Szklarczyk D, Botas J, Cantalapiedra CP, Giner-Lamia J, Mende DR, Kirsch R, Rattei T, Letunic I, Jensen LJ, Bork P, von Mering C, Huerta-Cepas J
2023 Jan 6; 51: D389-D394. PubMed: 36399505.
Abstract + PDFThe eggNOG (evolutionary gene genealogy Non-supervised Orthologous Groups) database is a bioinformatics resource providing orthology data and comprehensive functional information for organisms from all domains of life. Here, we present a major update of the database and website (version 6.0), which increases the number of covered organisms to 12 535 reference species, expands functional annotations, and implements new functionality. In total, eggNOG 6.0 provides a hierarchy of over 17M orthologous groups (OGs) computed at 1601 taxonomic levels, spanning 10 756 bacterial, 457 archaeal and 1322 eukaryotic organisms. OGs have been thoroughly annotated using recent knowledge from functional databases, including KEGG, Gene Ontology, UniProtKB, BiGG, CAZy, CARD, PFAM and SMART. eggNOG also offers phylogenetic trees for all OGs, maximising utility and versatility for end users while allowing researchers to investigate the evolutionary history of speciation and duplication events as well as the phylogenetic distribution of functional terms within each OG. Furthermore, the eggNOG 6.0 website contains new functionality to mine orthology and functional data with ease, including the possibility of generating phylogenetic profiles for multiple OGs across species or identifying single-copy OGs at custom taxonomic levels. eggNOG 6.0 is available at http://eggnog6.embl.de.
697.
Questioning the fetal microbiome illustrates pitfalls of low-biomass microbial studies.
Kennedy KM, de Goffau MC, Perez-Muñoz ME, Arrieta MC, Bäckhed F, Bork P, Braun T, Bushman FD, Dore J, de Vos WM, Earl AM, Eisen JA, Elovitz MA, Ganal-Vonarburg SC, Gänzle MG, Garrett WS, Hall LJ, Hornef MW, Huttenhower C, Konnikova L, Lebeer S, Macpherson AJ, Massey RC, McHardy AC, Koren O, Lawley TD, Ley RE, O\'Mahony L, O\'Toole PW, Pamer EG, Parkhill J, Raes J, Rattei T, Salonen A, Segal E, Segata N, Shanahan F, Sloboda DM, Smith GCS, Sokol H, Spector TD, Surette MG, Tannock GW, Walker AW, Yassour M, Walter J
AbstractWhether the human fetus and the prenatal intrauterine environment (amniotic fluid and placenta) are stably colonized by microbial communities in a healthy pregnancy remains a subject of debate. Here we evaluate recent studies that characterized microbial populations in human fetuses from the perspectives of reproductive biology, microbial ecology, bioinformatics, immunology, clinical microbiology and gnotobiology, and assess possible mechanisms by which the fetus might interact with microorganisms. Our analysis indicates that the detected microbial signals are likely the result of contamination during the clinical procedures to obtain fetal samples or during DNA extraction and DNA sequencing. Furthermore, the existence of live and replicating microbial populations in healthy fetal tissues is not compatible with fundamental concepts of immunology, clinical microbiology and the derivation of germ-free mammals. These conclusions are important to our understanding of human immune development and illustrate common pitfalls in the microbial analyses of many other low-biomass environments. The pursuit of a fetal microbiome serves as a cautionary example of the challenges of sequence-based microbiome studies when biomass is low or absent, and emphasizes the need for a trans-disciplinary approach that goes beyond contamination controls by also incorporating biological, ecological and mechanistic concepts.
696.
Enterotypes of the human gut mycobiome.
2023 Aug 11; 11(1): 179. PubMed: 37563687.
Abstract + PDFThe fungal component of the human gut microbiome, also known as the mycobiome, plays a vital role in intestinal ecology and human health. However, the overall structure of the gut mycobiome as well as the inter-individual variations in fungal composition remains largely unknown. In this study, we collected a total of 3363 fungal sequencing samples from 16 cohorts across three continents, including 572 newly profiled samples from China.
695.
InterPro in 2022.
Paysan-Lafosse T, Blum M, Chuguransky S, Grego T, Pinto BL, Salazar GA, Bileschi ML, Bork P, Bridge A, Colwell L, Gough J, Haft DH, Letunic I, Marchler-Bauer A, Mi H, Natale DA, Orengo CA, Pandurangan AP, Rivoire C, Sigrist CJA, Sillitoe I, Thanki N, Thomas PD, Tosatto SCE, Wu CH, Bateman A
2023 Jan 6; 51: D418-D427. PubMed: 36350672.
Abstract + PDFThe InterPro database (https://www.ebi.ac.uk/interpro/) provides an integrative classification of protein sequences into families, and identifies functionally important domains and conserved sites. Here, we report recent developments with InterPro (version 90.0) and its associated software, including updates to data content and to the website. These developments extend and enrich the information provided by InterPro, and provide a more user friendly access to the data. Additionally, we have worked on adding Pfam website features to the InterPro website, as the Pfam website will be retired in late 2022. We also show that InterPro's sequence coverage has kept pace with the growth of UniProtKB. Moreover, we report the development of a card game as a method of engaging the non-scientific community. Finally, we discuss the benefits and challenges brought by the use of artificial intelligence for protein structure prediction.
694.
Ocean-wide comparisons of mesopelagic planktonic community structures.
Rigonato J, Budinich M, Murillo AA, Brandão MC, Pierella Karlusich JJ, Soviadan YD, Gregory AC, Endo H, Kokoszka F, Vik D, Henry N, Frémont P, Labadie K, Zayed AA, Dimier C, Picheral M, Searson S, Poulain J, Kandels S, Pesant S, Karsenti E, Tara Oceans coordinators , Bork P, Bowler C, De Vargas C, Eveillard D, Gehlen M, Iudicone D, Lombard F, Ogata H, Stemmann L, Sullivan MB, Sunagawa S, Wincker P, Chaffron S, Jaillon O
2023 Aug 18; 3(1): 83. PubMed: 37596349.
Abstract + PDFFor decades, marine plankton have been investigated for their capacity to modulate biogeochemical cycles and provide fishery resources. Between the sunlit (epipelagic) layer and the deep dark waters, lies a vast and heterogeneous part of the ocean: the mesopelagic zone. How plankton composition is shaped by environment has been well-explored in the epipelagic but much less in the mesopelagic ocean. Here, we conducted comparative analyses of trans-kingdom community assemblages thriving in the mesopelagic oxygen minimum zone (OMZ), mesopelagic oxic, and their epipelagic counterparts. We identified nine distinct types of intermediate water masses that correlate with variation in mesopelagic community composition. Furthermore, oxygen, NO and particle flux together appeared as the main drivers governing these communities. Novel taxonomic signatures emerged from OMZ while a global co-occurrence network analysis showed that about 70% of the abundance of mesopelagic plankton groups is organized into three community modules. One module gathers prokaryotes, pico-eukaryotes and Nucleo-Cytoplasmic Large DNA Viruses (NCLDV) from oxic regions, and the two other modules are enriched in OMZ prokaryotes and OMZ pico-eukaryotes, respectively. We hypothesize that OMZ conditions led to a diversification of ecological niches, and thus communities, due to selective pressure from limited resources. Our study further clarifies the interplay between environmental factors in the mesopelagic oxic and OMZ, and the compositional features of communities.
693.
Computational exploration of the global microbiome for antibiotic discovery.
Santos-Júnior CD, Torres MDT, Duan Y, Rodríguez Del Río Á, Schmidt TSB, Chong H, Fullam A, Michael K, Zhu C, Houseman A, Somborski J, Vines A, Zhao XM, Bork P, Huerta-Cepas J, de la Fuente-Nunez C, Coelho LP
AbstractNovel antibiotics are urgently needed to combat the antibiotic-resistance crisis. We present a machine learning-based approach to predict prokaryotic antimicrobial peptides (AMPs) by leveraging a vast dataset of 63,410 metagenomes and 87,920 microbial genomes. This led to the creation of AMPSphere, a comprehensive catalog comprising 863,498 non-redundant peptides, the majority of which were previously unknown. We observed that AMP production varies by habitat, with animal-associated samples displaying the highest proportion of AMPs compared to other habitats. Furthermore, within different human-associated microbiota, strain-level differences were evident. To validate our predictions, we synthesized and experimentally tested 50 AMPs, demonstrating their efficacy against clinically relevant drug-resistant pathogens both in vitro and in vivo. These AMPs exhibited antibacterial activity by targeting the bacterial membrane. Additionally, AMPSphere provides valuable insights into the evolutionary origins of peptides. In conclusion, our approach identified AMP sequences within prokaryotic microbiomes, opening up new avenues for the discovery of antibiotics.
692.
Long-Read Sequencing Reveals Extensive DNA Methylations in Human Gut Phagenome Contributed by Prevalently Phage-Encoded Methyltransferases.
2023 Sep 29; 10(25): e2302159. PubMed: 37382405.
Abstract + PDFDNA methylation plays a crucial role in the survival of bacteriophages (phages), yet the understanding of their genome methylation remains limited. In this study, DNA methylation patterns are analyzed in 8848 metagenome-assembled high-quality phages from 104 fecal samples using single-molecule real-time sequencing. The results demonstrate that 97.60% of gut phages exhibit methylation, with certain factors correlating with methylation densities. Phages with higher methylation densities appear to have potential viability advantages. Strikingly, more than one-third of the phages possess their own DNA methyltransferases (MTases). Increased MTase copies are associated with higher genome methylation densities, specific methylation motifs, and elevated prevalence of certain phage groups. Notably, the majority of these MTases share close homology with those encoded by gut bacteria, suggesting their exchange during phage-bacterium interactions. Furthermore, these MTases can be employed to accurately predict phage-host relationships. Overall, the findings indicate the widespread utilization of DNA methylation by gut DNA phages as an evasion mechanism against host defense systems, with a substantial contribution from phage-encoded MTases.
691.
The STRING database in 2023: protein-protein association networks and functional enrichment analyses for any sequenced genome of interest.
Szklarczyk D, Kirsch R, Koutrouli M, Nastou K, Mehryary F, Hachilif R, Gable AL, Fang T, Doncheva NT, Pyysalo S, Bork P, Jensen LJ, von Mering C
2023 Jan 6; 51: D638-D646. PubMed: 36370105.
Abstract + PDFMuch of the complexity within cells arises from functional and regulatory interactions among proteins. The core of these interactions is increasingly known, but novel interactions continue to be discovered, and the information remains scattered across different database resources, experimental modalities and levels of mechanistic detail. The STRING database (https://string-db.org/) systematically collects and integrates protein-protein interactions-both physical interactions as well as functional associations. The data originate from a number of sources: automated text mining of the scientific literature, computational interaction predictions from co-expression, conserved genomic context, databases of interaction experiments and known complexes/pathways from curated sources. All of these interactions are critically assessed, scored, and subsequently automatically transferred to less well-studied organisms using hierarchical orthology information. The data can be accessed via the website, but also programmatically and via bulk downloads. The most recent developments in STRING (version 12.0) are: (i) it is now possible to create, browse and analyze a full interaction network for any novel genome of interest, by submitting its complement of encoded proteins, (ii) the co-expression channel now uses variational auto-encoders to predict interactions, and it covers two new sources, single-cell RNA-seq and experimental proteomics data and (iii) the confidence in each experimentally derived interaction is now estimated based on the detection method used, and communicated to the user in the web-interface. Furthermore, STRING continues to enhance its facilities for functional enrichment analysis, which are now fully available also for user-submitted genomes.
690.
SPHINGOLIPIDS ARE DEPLETED IN ALCOHOL-RELATED LIVER FIBROSIS.
Thiele M, Suvitaival T, Trošt K, Kim M, de Zawadzki A, Kjaergaard M, Rasmussen DN, Lindvig KP, Israelsen M, Detlefsen S, Andersen P, Juel HB, Nielsen T, Georgiou S, Filippa V, Kuhn M, Nishijima S, Moitinho-Silva L, Rossing P, Trebicka J, Anastasiadou E, Bork P, Hansen T, Quigley CL, Krag A, MicrobLiver , GALAXY Consortia
2023 Jun 26; 164(7): 1248-1260. PubMed: 36849086.
Abstract + PDFAlcohol disturbs hepatic lipid synthesis and transport, but the role of lipid dysfunction in alcohol-related liver disease (ALD) is unclear. In this biopsy-controlled, prospective, observational study, we characterized the liver and plasma lipidomes in patients with early ALD.
689.
Consistency across multi-omics layers in a drug-perturbed gut microbial community.
Wuyts S, Alves R, Zimmermann-Kogadeeva M, Nishijima S, Blasche S, Driessen M, Geyer PE, Hercog R, Kartal E, Maier L, Müller JB, Garcia Santamarina S, Schmidt TSB, Sevin DC, Telzerow A, Treit PV, Wenzel T, Typas A, Patil KR, Mann M, Kuhn M, Bork P
2023 Sep 12; 19(9): e11525. PubMed: 37485738.
Abstract + PDFMulti-omics analyses are used in microbiome studies to understand molecular changes in microbial communities exposed to different conditions. However, it is not always clear how much each omics data type contributes to our understanding and whether they are concordant with each other. Here, we map the molecular response of a synthetic community of 32 human gut bacteria to three non-antibiotic drugs by using five omics layers (16S rRNA gene profiling, metagenomics, metatranscriptomics, metaproteomics and metabolomics). We find that all the omics methods with species resolution are highly consistent in estimating relative species abundances. Furthermore, different omics methods complement each other for capturing functional changes. For example, while nearly all the omics data types captured that the antipsychotic drug chlorpromazine selectively inhibits Bacteroidota representatives in the community, the metatranscriptome and metaproteome suggested that the drug induces stress responses related to protein quality control. Metabolomics revealed a decrease in oligosaccharide uptake, likely caused by Bacteroidota depletion. Our study highlights how multi-omics datasets can be utilized to reveal complex molecular responses to external perturbations in microbial communities.
2022 19 publication(s).
688.
Structure and function of DNA transposition assemblies involved in antibiotic resistance spreading.
Barabas O, Smyshlyaev G, Isbilir B, Khedkar S, Rojas-Cordova C, Bateman AG, Bork P
AbstractTransposons are mobile genetic elements that drive evolution and adaptation throughout the tree of life. In bacteria, they often transfer antibiotic resistance genes and contribute to the emergence of multidrug-resistant pathogens. In this talk, I will present our recent discoveries on a group of transposons that efficiently propagate antibiotic resistance genes across diverse microbial communities. Using a dedicated computational pipeline, we mapped the most wide-spread transposons in bacterial genomes and characterized their diversity, genetic cargo, and transfer dynamics. Selected elements were experimentally reconstituted to describe their molecular mechanisms and biochemical pathways. We determined numerous high-resolution crystal and cryo-EM structures of the protein-DNA assemblies involved in transposon movement. The structures capture various stages of transposition and reveal an intricate interplay between the core transposition machinery and host-encoded proteins. Protein interactions shape transposon and genomic DNA in unique ways to cut, exchange and re-join strands in a tightly regulated manner. Importantly, our data also explain how specific DNA distortion and cleavage mechanisms enable the transposons to move between diverse genomic sites, expanding gene transfer across many species. These results shed new light onto the molecular strategies of antibiotic resistance carrying transposons and show how they evolved to effectively spread key genetic traits. Our insights also open new opportunities to develop strategies for blocking transposition and thereby help control resistance spreading.
687.
Impairment of gut microbial biotin metabolism and host biotin status in severe obesity: effect of biotin and prebiotic supplementation on improved metabolism.
Belda E, Voland L, Tremaroli V, Falony G, Adriouch S, Assmann KE, Prifiti E, Aron-Wisnewsky J, Debédat J, Le Roy T, Nielsen T, Amouyal C, André S, Andreelli F, Blüher M, Chakaroun R, Chilloux J, Coelho LP, Dao MC, Das P, Fellahi S, Forslund S, Galleron N, Hansen TH, Holmes B, Ji B, Krogh Pedersen H, Le P, Le Chatelier E, Lewinter C, Mannerås-Holm L, Marquet F, Myridakis A, Pelloux V, Pons N, Quinquis B, Rouault C, Roume H, Salem JE, Sokolovska N, Søndertoft NB, Touch S, Vieira-Silva S, MetaCardis Consortium , Galan P, Holst J, Gøtze JP, Køber L, Vestergaard H, Hansen T, Hercberg S, Oppert JM, Nielsen J, Letunic I, Dumas ME, Stumvoll M, Pedersen OB, Bork P, Ehrlich SD, Zucker JD, Bäckhed F, Raes J, Clément K
Abstract + PDFGut microbiota is a key component in obesity and type 2 diabetes, yet mechanisms and metabolites central to this interaction remain unclear. We examined the human gut microbiome's functional composition in healthy metabolic state and the most severe states of obesity and type 2 diabetes within the MetaCardis cohort. We focused on the role of B vitamins and B7/B8 biotin for regulation of host metabolic state, as these vitamins influence both microbial function and host metabolism and inflammation.
686.
Towards the biogeography of prokaryotic genes.
Coelho LP, Alves RJ, Del Río ÁR, Myers PN, Cantalapiedra CP, Giner-Lamia J, Schmidt TSB, Mende DR, Orakov A, Letunic I, Hildebrand F, Van Rossum T, Forslund SK, Khedkar S, Maistrenko OM, Pan S, Jia L, Ferretti P, Sunagawa S, Zhao XM, Nielsen HB, Huerta-Cepas J, Bork P
Abstract + PDFMicrobial genes encode the majority of the functional repertoire of life on earth. However, despite increasing efforts in metagenomic sequencing of various habitats, little is known about the distribution of genes across the global biosphere, with implications for human and planetary health. Here we constructed a non-redundant gene catalogue of 303 million species-level genes (clustered at 95% nucleotide identity) from 13,174 publicly available metagenomes across 14 major habitats and use it to show that most genes are specific to a single habitat. The small fraction of genes found in multiple habitats is enriched in antibiotic-resistance genes and markers for mobile genetic elements. By further clustering these species-level genes into 32 million protein families, we observed that a small fraction of these families contain the majority of the genes (0.6% of families account for 50% of the genes). The majority of species-level genes and protein families are rare. Furthermore, species-level genes, and in particular the rare ones, show low rates of positive (adaptive) selection, supporting a model in which most genetic variability observed within each protein family is neutral or nearly neutral.
685.
Microbiome and metabolome features of the cardiometabolic disease spectrum.
Fromentin S, Forslund SK, Chechi K, Aron-Wisnewsky J, Chakaroun R, Nielsen T, Tremaroli V, Ji B, Prifti E, Myridakis A, Chilloux J, Andrikopoulos P, Fan Y, Olanipekun MT, Alves RJ, Adiouch S, Bar N, Talmor-Barkan Y, Belda E, Caesar R, Coelho LP, Falony G, Fellahi S, Galan P, Galleron N, Helft G, Hoyles L, Isnard R, Le Chatelier E, Julienne H, Olsson L, Pedersen HK, Pons N, Quinquis B, Rouault C, Roume H, Salem JE, Schmidt TSB, Vieira-Silva S, Li P, Zimmermann-Kogadeeva M, Lewinter C, Søndertoft NB, Hansen TH, Gauguier D, Gøtze JP, Køber L, Kornowski R, Vestergaard H, Hansen T, Zucker JD, Hercberg S, Letunic I, Bäckhed F, Oppert JM, Nielsen J, Raes J, Bork P, Stumvoll M, Segal E, Clément K, Dumas ME, Ehrlich SD, Pedersen O
Abstract + PDFPrevious microbiome and metabolome analyses exploring non-communicable diseases have paid scant attention to major confounders of study outcomes, such as common, pre-morbid and co-morbid conditions, or polypharmacy. Here, in the context of ischemic heart disease (IHD), we used a study design that recapitulates disease initiation, escalation and response to treatment over time, mirroring a longitudinal study that would otherwise be difficult to perform given the protracted nature of IHD pathogenesis. We recruited 1,241 middle-aged Europeans, including healthy individuals, individuals with dysmetabolic morbidities (obesity and type 2 diabetes) but lacking overt IHD diagnosis and individuals with IHD at three distinct clinical stages-acute coronary syndrome, chronic IHD and IHD with heart failure-and characterized their phenome, gut metagenome and serum and urine metabolome. We found that about 75% of microbiome and metabolome features that distinguish individuals with IHD from healthy individuals after adjustment for effects of medication and lifestyle are present in individuals exhibiting dysmetabolism, suggesting that major alterations of the gut microbiome and metabolome might begin long before clinical onset of IHD. We further categorized microbiome and metabolome signatures related to prodromal dysmetabolism, specific to IHD in general or to each of its three subtypes or related to escalation or de-escalation of IHD. Discriminant analysis based on specific IHD microbiome and metabolome features could better differentiate individuals with IHD from healthy individuals or metabolically matched individuals as compared to the conventional risk markers, pointing to a pathophysiological relevance of these features.
684.
A faecal microbiota signature with high specificity for pancreatic cancer.
Kartal E, Schmidt TSB, Molina-Montes E, Rodríguez-Perales S, Wirbel J, Maistrenko OM, Akanni WA, Alashkar Alhamwe B, Alves RJ, Carrato A, Erasmus HP, Estudillo L, Finkelmeier F, Fullam A, Glazek AM, Gómez-Rubio P, Hercog R, Jung F, Kandels S, Kersting S, Langheinrich M, Márquez M, Molero X, Orakov A, Van Rossum T, Torres-Ruiz R, Telzerow A, Zych K, MAGIC Study investigators , PanGenEU Study investigators , Benes V, Zeller G, Trebicka J, X Real F, Malats N, Bork P
Abstract + PDFRecent evidence suggests a role for the microbiome in pancreatic ductal adenocarcinoma (PDAC) aetiology and progression.
683.
Landscape of mobile genetic elements and their antibiotic resistance cargo in prokaryotic genomes.
Khedkar S, Smyshlyaev G, Letunic I, Maistrenko OM, Coelho LP, Orakov A, Forslund SK, Hildebrand F, Luetge M, Schmidt TSB, Barabas O, Bork P
2022 Apr 8; 50(6): 3155-3168. PubMed: 35323968.
Abstract + PDFProkaryotic Mobile Genetic Elements (MGEs) such as transposons, integrons, phages and plasmids, play important roles in prokaryotic evolution and in the dispersal of cargo functions like antibiotic resistance. However, each of these MGE types is usually annotated and analysed individually, hampering a global understanding of phylogenetic and environmental patterns of MGE dispersal. We thus developed a computational framework that captures diverse MGE types, their cargos and MGE-mediated horizontal transfer events, using recombinases as ubiquitous MGE marker genes and pangenome information for MGE boundary estimation. Applied to ∼84k genomes with habitat annotation, we mapped 2.8 million MGE-specific recombinases to six operational MGE types, which together contain on average 13% of all the genes in a genome. Transposable elements (TEs) dominated across all taxa (∼1.7 million occurrences), outnumbering phages and phage-like elements (<0.4 million). We recorded numerous MGE-mediated horizontal transfer events across diverse phyla and habitats involving all MGE types, disentangled and quantified the extent of hitchhiking of TEs (17%) and integrons (63%) with other MGE categories, and established TEs as dominant carriers of antibiotic resistance genes. We integrated all these findings into a resource (proMGE.embl.de), which should facilitate future studies on the large mobile part of genomes and its horizontal dispersal.
682.
Meconium Microbiome of Very Preterm Infants across Germany.
Klopp J, Ferretti P, Meyer CU, Hilbert K, Haiß A, Marißen J, Henneke P, Hudalla H, Pirr S, Viemann D, Zemlin M, Forslund SK, Härtel C, Bork P, Gehring S, Van Rossum T, and the PRIMAL Consortium
Abstract + PDFMeconium constitutes infants' first bowel movements postnatally. The consistency and microbial load of meconium are different from infant and adult stool. While recent evidence suggests that meconium is sterile , rapid colonization occurs after birth. The meconium microbiome has been associated with negative health outcomes, but its composition is not well described, especially in preterm infants. Here, we characterized the meconium microbiomes from 330 very preterm infants (gestational ages 28 to 32 weeks) from 15 hospitals in Germany and in fecal samples from a subset of their mothers (N = 217). Microbiome profiles were compiled using 16S rRNA gene sequencing with negative and positive controls. The meconium microbiome was dominated by , Staphylococcus, and spp. and was associated with gestational age at birth and age at sample collection. Bifidobacterial abundance was negatively correlated with potentially pathogenic genera. The amount of bacterial DNA in meconium samples varied greatly across samples and was associated with the time since birth but not with gestational age or hospital site. In samples with low bacterial load, human mitochondrial sequences were highly amplified using commonly used, bacterial-targeted 16S rRNA primers. Only half of the meconium samples contained sufficient bacterial material to study the microbiome using a standard approach. To facilitate future meconium studies, we present a five-level scoring system ("MecBac") that predicts the success of 16S rRNA bacterial sequencing for meconium samples. These findings provide a foundational characterization of an understudied portion of the human microbiome and will aid the design of future meconium microbiome studies. Meconium is present in the intestines of infants before and after birth and constitutes their first bowel movements postnatally. The consistency, composition and microbial load of meconium is largely different from infant and adult stool. While recent evidence suggests that meconium is sterile , rapid colonization occurs after birth. The meconium microbiome has been associated with short-term and long-term negative health outcomes, but its composition is not yet well described, especially in preterm infants. We provide a characterization of the microbiome structure and composition of infant meconium and maternal feces from a large study cohort and propose a method to evaluate meconium samples for bacterial sequencing suitability. These findings provide a foundational characterization of an understudied portion of the human microbiome and will aid the design of future meconium microbiome studies.
681.
Alterations of oral microbiota and impact on the gut microbiome in type 1 diabetes mellitus revealed by integrated multi-omic analyses.
Kunath BJ, Hickl O, Queirós P, Martin-Gallausiaux C, Lebrun LA, Halder R, Laczny CC, Schmidt TSB, Hayward MR, Becher D, Heintz-Buschart A, de Beaufort C, Bork P, May P, Wilmes P
2022 Dec 28; 10(1): 243. PubMed: 36578059.
Abstract + PDFAlterations to the gut microbiome have been linked to multiple chronic diseases. However, the drivers of such changes remain largely unknown. The oral cavity acts as a major route of exposure to exogenous factors including pathogens, and processes therein may affect the communities in the subsequent compartments of the gastrointestinal tract. Here, we perform strain-resolved, integrated meta-genomic, transcriptomic, and proteomic analyses of paired saliva and stool samples collected from 35 individuals from eight families with multiple cases of type 1 diabetes mellitus (T1DM).
680.
Metagenomic identification of microbial signatures predicting pancreatic cancer from a multinational study.
Nagata N, Nishijima S, Kojima Y, Hisada Y, Imbe K, Miyoshi-Akiyama T, Suda W, Kimura M, Aoki R, Sekine K, Ohsugi M, Miki K, Osawa T, Ueki K, Oka S, Mizokami M, Kartal E, Schmidt TSB, Molina-Montes E, Estudillo L, Malats N, Trebicka J, Kersting S, Langheinrich M, Bork P, Uemura N, Itoi T, Kawai T
2022 Jul 8; 163(1): 222-238. PubMed: 35398347.
Abstract + PDFTo identify gut and oral metagenomic signatures that accurately predict pancreatic ductal carcinoma (PDAC) and to validate these signatures in independent cohorts.
679.
Biosynthetic potential of the global ocean microbiome.
Paoli L, Ruscheweyh HJ, Forneris CC, Hubrich F, Kautsar S, Bhushan A, Lotti A, Clayssen Q, Salazar G, Milanese A, Carlström CI, Papadopoulou C, Gehrig D, Karasikov M, Mustafa H, Larralde M, Carroll LM, Sánchez P, Zayed AA, Cronin DR, Acinas SG, Bork P, Bowler C, Delmont TO, Gasol JM, Gossert AD, Kahles A, Sullivan MB, Wincker P, Zeller G, Robinson SL, Piel J, Sunagawa S
Abstract + PDFNatural microbial communities are phylogenetically and metabolically diverse. In addition to underexplored organismal groups, this diversity encompasses a rich discovery potential for ecologically and biotechnologically relevant enzymes and biochemical compounds. However, studying this diversity to identify genomic pathways for the synthesis of such compounds and assigning them to their respective hosts remains challenging. The biosynthetic potential of microorganisms in the open ocean remains largely uncharted owing to limitations in the analysis of genome-resolved data at the global scale. Here we investigated the diversity and novelty of biosynthetic gene clusters in the ocean by integrating around 10,000 microbial genomes from cultivated and single cells with more than 25,000 newly reconstructed draft genomes from more than 1,000 seawater samples. These efforts revealed approximately 40,000 putative mostly new biosynthetic gene clusters, several of which were found in previously unsuspected phylogenetic groups. Among these groups, we identified a lineage rich in biosynthetic gene clusters ('Candidatus Eudoremicrobiaceae') that belongs to an uncultivated bacterial phylum and includes some of the most biosynthetically diverse microorganisms in this environment. From these, we characterized the phospeptin and pythonamide pathways, revealing cases of unusual bioactive compound structure and enzymology, respectively. Together, this research demonstrates how microbiomics-driven strategies can enable the investigation of previously undescribed enzymes and natural products in underexplored microbial groups and environments.
678.
Enrichment of gut microbiome strains for cultivation-free genome sequencing using droplet microfluidics.
2022 Jan 24; 2(1): None. PubMed: 35118437.
Abstract + PDFWe report a droplet microfluidic method to target and sort individual cells directly from complex microbiome samples and to prepare these cells for bulk whole-genome sequencing without cultivation. We characterize this approach by recovering bacteria spiked into human stool samples at a ratio as low as 1:250 and by successfully enriching endogenous to the level required for de novo assembly of high-quality genomes. Although microbiome strains are increasingly demanded for biomedical applications, a vast majority of species and strains are uncultivated and without reference genomes. We address this shortcoming by encapsulating complex microbiome samples directly into microfluidic droplets and amplifying a target-specific genomic fragment using a custom molecular TaqMan probe. We separate those positive droplets by droplet sorting, selectively enriching single target strain cells. Finally, we present a protocol to purify the genomic DNA while specifically removing amplicons and cell debris for high-quality genome sequencing.
677.
Genomic evidence for global ocean plankton biogeography shaped by large-scale current systems.
Richter DJ, Watteaux R, Vannier T, Leconte J, Frémont P, Reygondeau G, Maillet N, Henry N, Benoit G, Da Silva O, Delmont TO, Fernàndez-Guerra A, Suweis S, Narci R, Berney C, Eveillard D, Gavory F, Guidi L, Labadie K, Mahieu E, Poulain J, Romac S, Roux S, Dimier C, Kandels S, Picheral M, Searson S, Tara Oceans
Coordinators , Pesant S, Aury JM, Brum JR, Lemaitre C, Pelletier E, Bork P, Sunagawa S, Lombard F, Karp-Boss L, Bowler C, Sullivan MB, Karsenti E, Mariadassou M, Probert I, Peterlongo P, Wincker P, De Vargas C, d'Alcalà MR, Iudicone D, Jaillon O
Abstract + PDFBiogeographical studies have traditionally focused on readily visible organisms, but recent technological advances are enabling analyses of the large-scale distribution of microscopic organisms, whose biogeographical patterns have long been debated. Here we assessed the global structure of plankton geography and its relation to the biological, chemical, and physical context of the ocean (the 'seascape') by analyzing metagenomes of plankton communities sampled across oceans during the Oceans expedition, in light of environmental data and ocean current transport. Using a consistent approach across organismal sizes that provides unprecedented resolution to measure changes in genomic composition between communities, we report a pan-ocean, size-dependent plankton biogeography overlying regional heterogeneity. We found robust evidence for a basin-scale impact of transport by ocean currents on plankton biogeography, and on a characteristic timescale of community dynamics going beyond simple seasonality or life history transitions of plankton.
676.
Cultivation-independent genomes greatly expand taxonomic-profiling capabilities of mOTUs across various environments.
Ruscheweyh HJ, Milanese A, Paoli L, Karcher N, Clayssen Q, Keller MI, Wirbel J, Bork P, Mende DR, Zeller G, Sunagawa S
2022 Dec 5; 10(1): 212. PubMed: 36464731.
Abstract + PDFTaxonomic profiling is a fundamental task in microbiome research that aims to detect and quantify the relative abundance of microorganisms in biological samples. Available methods using shotgun metagenomic data generally depend on the deposition of sequenced and taxonomically annotated genomes, usually from cultures of isolated strains, in reference databases (reference genomes). However, the majority of microorganisms have not been cultured yet. Thus, a substantial fraction of microbial community members remains unaccounted for during taxonomic profiling, particularly in samples from underexplored environments. To address this issue, we developed the mOTU profiler, a tool that enables reference genome-independent species-level profiling of metagenomes. As such, it supports the identification and quantification of both "known" and "unknown" species based on a set of select marker genes.
675.
Dissecting the intracellular pancreatic tumor microbiome at single-cell level.
Schmidt TSB, Bork P
2022 Oct 10; 40(10): 1083-1085. PubMed: 36179685.
AbstractMicroorganisms play a role in the progression of various cancers. In this issue of Cancer Cell, Ghaddar et al. traced bacteria in pancreatic tumors at single-cell resolution and associated their intracellular presence with cell-type-specific transcriptional shifts, with links to clinical prognosis.
674.
Drivers and determinants of strain dynamics following fecal microbiota transplantation.
Schmidt TSB, Li SS, Maistrenko OM, Akanni W, Coelho LP, Dolai S, Fullam A, Glazek AM, Hercog R, Herrema H, Jung F, Kandels S, Orakov A, Thielemann R, von Stetten M, Van Rossum T, Benes V, Borody TJ, de Vos WM, Ponsioen CY, Nieuwdorp M, Bork P
Abstract + PDFFecal microbiota transplantation (FMT) is a therapeutic intervention for inflammatory diseases of the gastrointestinal tract, but its clinical mode of action and subsequent microbiome dynamics remain poorly understood. Here we analyzed metagenomes from 316 FMTs, sampled pre and post intervention, for the treatment of ten different disease indications. We quantified strain-level dynamics of 1,089 microbial species, complemented by 47,548 newly constructed metagenome-assembled genomes. Donor strain colonization and recipient strain resilience were mostly independent of clinical outcomes, but accurately predictable using LASSO-regularized regression models that accounted for host, microbiome and procedural variables. Recipient factors and donor-recipient complementarity, encompassing entire microbial communities to individual strains, were the main determinants of strain population dynamics, providing insights into the underlying processes that shape the post-FMT gut microbiome. Applying an ecology-based framework to our findings indicated parameters that may inform the development of more effective, targeted microbiome therapies in the future, and suggested how patient stratification can be used to enhance donor microbiota colonization or the displacement of recipient microbes in clinical practice.
673.
metaSNV v2: detection of SNVs and subspecies in prokaryotic metagenomes.
2022 Jan 27; 38(4): 1162-1164. PubMed: 34791031.
Abstract + PDFTaxonomic analysis of microbial communities is well supported at the level of species and strains. However, species can contain significant phenotypic diversity and strains are rarely widely shared across global populations. Stratifying the diversity between species and strains can identify "subspecies", which are a useful intermediary. High-throughput identification and profiling of subspecies is not yet supported in the microbiome field. Here, we use an operational definition of subspecies based on SNV patterns within species to identify and profile subspecies in metagenomes, along with their distinctive SNVs and genes. We incorporate this method into metaSNV v2, which extends existing SNV-calling software to support further SNV interpretation for population genetics. These new features support microbiome analyses to link SNV profiles with host phenotype or environment and niche-specificity. We demonstrate subspecies identification in marine and faecal metagenomes. In the latter, we analyse 70 species in 7,524 adult and infant subjects, supporting a common subspecies population structure in the human gut microbiome and illustrating some limits in subspecies calling.
672.
Visualizing translation dynamics at atomic detail inside a bacterial cell.
Xue L, Lenz S, Zimmermann-Kogadeeva M, Tegunov D, Cramer P, Bork P, Rappsilber J, Mahamid J
Abstract + PDFTranslation is the fundamental process of protein synthesis and is catalysed by the ribosome in all living cells. Here we use advances in cryo-electron tomography and sub-tomogram analysis to visualize the structural dynamics of translation inside the bacterium Mycoplasma pneumoniae. To interpret the functional states in detail, we first obtain a high-resolution in-cell average map of all translating ribosomes and build an atomic model for the M. pneumoniae ribosome that reveals distinct extensions of ribosomal proteins. Classification then resolves 13 ribosome states that differ in their conformation and composition. These recapitulate major states that were previously resolved in vitro, and reflect intermediates during active translation. On the basis of these states, we animate translation elongation inside native cells and show how antibiotics reshape the cellular translation landscapes. During translation elongation, ribosomes often assemble in defined three-dimensional arrangements to form polysomes. By mapping the intracellular organization of translating ribosomes, we show that their association into polysomes involves a local coordination mechanism that is mediated by the ribosomal protein L9. We propose that an extended conformation of L9 within polysomes mitigates collisions to facilitate translation fidelity. Our work thus demonstrates the feasibility of visualizing molecular processes at atomic detail inside cells.
671.
Publisher Correction: Visualizing translation dynamics at atomic detail inside a bacterial cell.
Xue L, Lenz S, Zimmermann-Kogadeeva M, Tegunov D, Cramer P, Bork P, Rappsilber J, Mahamid J
PDF670.
Cryptic and abundant marine viruses at the evolutionary origins of Earth's RNA virome.
Zayed AA, Wainaina JM, Dominguez-Huerta G, Pelletier E, Guo J, Mohssen M, Tian F, Pratama AA, Bolduc B, Zablocki O, Cronin D, Solden L, Delage E, Alberti A, Aury JM, Carradec Q, Da Silva C, Labadie K, Poulain J, Ruscheweyh HJ, Salazar G, Shatoff E, Tara Oceans coordinators , Bundschuh R, Fredrick K, Kubatko LS, Chaffron S, Culley AI, Sunagawa S, Kuhn JH, Wincker P, Sullivan MB, Acinas S, Babin M, Bork P, Boss E, Bowler C, Cochrane G, De Vargas C, Gorsky G, Guidi L, Grimsley N, Hingamp P, Iudicone PD, Jaillon O, Kandels S, Karp-Boss L, Karsenti E, Not F, Ogata H, Poulton N, Pesant S, Sardet C, Speich S, Stemmann L, Sullivan MB, Sungawa S, Wincker P
AbstractWhereas DNA viruses are known to be abundant, diverse, and commonly key ecosystem players, RNA viruses are insufficiently studied outside disease settings. In this study, we analyzed ≈28 terabases of Global Ocean RNA sequences to expand Earth's RNA virus catalogs and their taxonomy, investigate their evolutionary origins, and assess their marine biogeography from pole to pole. Using new approaches to optimize discovery and classification, we identified RNA viruses that necessitate substantive revisions of taxonomy (doubling phyla and adding >50% new classes) and evolutionary understanding. "Species"-rank abundance determination revealed that viruses of the new phyla "," a missing link in early RNA virus evolution, and "" are widespread and dominant in the oceans. These efforts provide foundational knowledge critical to integrating RNA viruses into ecological and epidemiological models.
2021 34 publication(s).
669.
Deep ocean metagenomes provide insight into the metabolic architecture of bathypelagic microbial communities.
Acinas SG, Sánchez P, Salazar G, Cornejo-Castillo FM, Sebastián M, Logares R, Royo-Llonch M, Paoli L, Sunagawa S, Hingamp P, Ogata H, Lima-Mendez G, Roux S, González JM, Arrieta JM, Alam IS, Kamau A, Bowler C, Raes J, Pesant S, Bork P, Agustí S, Gojobori T, Vaqué D, Sullivan MB, Pedrós-Alió C, Massana R, Duarte CM, Gasol JM
2021 May 21; 4(1): 604. PubMed: 34021239.
Abstract + PDFThe deep sea, the largest ocean's compartment, drives planetary-scale biogeochemical cycling. Yet, the functional exploration of its microbial communities lags far behind other environments. Here we analyze 58 metagenomes from tropical and subtropical deep oceans to generate the Malaspina Gene Database. Free-living or particle-attached lifestyles drive functional differences in bathypelagic prokaryotic communities, regardless of their biogeography. Ammonia and CO oxidation pathways are enriched in the free-living microbial communities and dissimilatory nitrate reduction to ammonium and H oxidation pathways in the particle-attached, while the Calvin Benson-Bassham cycle is the most prevalent inorganic carbon fixation pathway in both size fractions. Reconstruction of the Malaspina Deep Metagenome-Assembled Genomes reveals unique non-cyanobacterial diazotrophic bacteria and chemolithoautotrophic prokaryotes. The widespread potential to grow both autotrophically and heterotrophically suggests that mixotrophy is an ecologically relevant trait in the deep ocean. These results expand our understanding of the functional microbial structure and metabolic capabilities of the largest Earth aquatic ecosystem.
668.
Disease severity-specific neutrophil signatures in blood transcriptomes stratify COVID-19 patients.
Aschenbrenner AC, Mouktaroudi M, Krämer B, Oestreich M, Antonakos N, Nuesch-Germano M, Gkizeli K, Bonaguro L, Reusch N, Baßler K, Saridaki M, Knoll R, Pecht T, Kapellos TS, Doulou S, Kröger C, Herbert M, Holsten L, Horne A, Gemünd ID, Rovina N, Agrawal S, Dahm K, van Uelft M, Drews A, Lenkeit L, Bruse N, Gerretsen J, Gierlich J, Becker M, Händler K, Kraut M, Theis H, Mengiste S, De Domenico E, Schulte-Schrepping J, Seep L, Raabe J, Hoffmeister C, ToVinh M, Keitel V, Rieke G, Talevi V, Skowasch D, Aziz NA, Pickkers P, van de Veerdonk FL, Netea MG, Schultze JL, Kox M, Breteler MMB, Nattermann J, Koutsoukou A, Giamarellos-Bourboulis EJ, Ulas T, German COVID-19 Omics Initiative (DeCOI) , Altmüller J, Angelov A, Bals R, Bartholomäus A, Becker A, Bitzer M, Bonifacio E, Bork P, Casadei N, Clavel T, Colome-Tatche M, Diefenbach A, Dilthey A, Fischer N, Förstner K, Franzenburg S, Frick JS, Gabernet G, Gagneur J, Ganzenmüller T, Göpel S, Goesmann A, Hain T, Heimbach A, Hummel M, Iftner A, Iftner T, Janssen S, Kalinowski J, Kallies R, Kehr B, Keller A, Kim-Hellmuth S, Klein C, Kohlbacher O, Köhrer K, Korbel J, Kühnert D, Kurth I, Landthaler M, Li Y, Ludwig K, Makarewicz O, Marz M, McHardy A, Mertes C, Nöthen M, Nürnberg P, Ohler U, Ossowski S, Overmann J, Pfeffer K, Poetsch AR, Pühler A, Rajewsky N, Ralser M, Rieß O, Ripke S, Nunes da Rocha U, Rosenstiel P, Saliba AE, Sander LE, Sawitzki B, Schiffer P, Schneider W, Schulte EC, Schultze JL, Sczyrba A, Singh Y, Sonnabend M, Stegle O, Stoye J, Theis F, Vehreschild J, Vogel J, von Kleist M, Walker A, Walter J, Wieczorek D, Winkler S, Ziebuhr J
2021 01 13; 13(1): 7. PubMed: 33441124.
Abstract + PDFThe SARS-CoV-2 pandemic is currently leading to increasing numbers of COVID-19 patients all over the world. Clinical presentations range from asymptomatic, mild respiratory tract infection, to severe cases with acute respiratory distress syndrome, respiratory failure, and death. Reports on a dysregulated immune system in the severe cases call for a better characterization and understanding of the changes in the immune system.
667.
Metagenomic assessment of the global diversity and distribution of bacteria and fungi.
2021 Jan; 23(1): 316-326. PubMed: 33185929.
Abstract + PDFBacteria and fungi are of uttermost importance in determining environmental and host functioning. Despite close interactions between animals, plants, their associated microbiomes, and the environment they inhabit, the distribution and role of bacteria and especially fungi across host and environments as well as the cross-habitat determinants of their community compositions remain little investigated. Using a uniquely broad global dataset of 13 483 metagenomes, we analysed the microbiome structure and function of 25 host-associated and environmental habitats, focusing on potential interactions between bacteria and fungi. We found that the metagenomic relative abundance ratio of bacteria-to-fungi is a distinctive microbial feature of habitats. Compared with fungi, the cross-habitat distribution pattern of bacteria was more strongly driven by habitat type. Fungal diversity was depleted in host-associated communities compared with those in the environment, particularly terrestrial habitats, whereas this diversity pattern was less pronounced for bacteria. The relative gene functional potential of bacteria or fungi reflected their diversity patterns and appeared to depend on a balance between substrate availability and biotic interactions. Alongside helping to identify hotspots and sources of microbial diversity, our study provides support for differences in assembly patterns and processes between bacterial and fungal communities across different habitats.
666.
Protein Intake, Metabolic Status and the Gut Microbiota in Different Ethnicities: Results from Two Independent Cohorts.
Bel Lassen P, Attaye I, Adriouch S, Nicolaou M, Aron-Wisnewsky J, Nielsen T, Chakaroun R, Le Chatelier E, Forslund S, Belda E, Bork P, Bäckhed F, Stumvoll M, Pedersen O, Herrema H, Groen AK, Pinto-Sietsma SJ, Zwinderman AH, Nieuwdorp M, Clement K, On Behalf Of Metacardis Consortium
Abstract + PDFProtein intake has been associated with the development of pre-diabetes (pre-T2D) and type 2 diabetes (T2D). The gut microbiota has the capacity to produce harmful metabolites derived from dietary protein. Furthermore, both the gut microbiota composition and metabolic status (e.g., insulin resistance) can be modulated by diet and ethnicity. However, to date most studies have predominantly focused on carbohydrate and fiber intake with regards to metabolic status and gut microbiota composition.
665.
The InterPro protein families and domains database: 20 years on.
Blum M, Chang HY, Chuguransky S, Grego T, Kandasaamy S, Mitchell A, Nuka G, Paysan-Lafosse T, Qureshi M, Raj S, Richardson L, Salazar GA, Williams L, Bork P, Bridge A, Gough J, Haft DH, Letunic I, Marchler-Bauer A, Mi H, Natale DA, Necci M, Orengo CA, Pandurangan AP, Rivoire C, Sigrist CJA, Sillitoe I, Thanki N, Thomas PD, Tosatto SCE, Wu CH, Bateman A, Finn RD
2021 Jan 8; 49(D1): D344-D354. PubMed: 33156333.
Abstract + PDFThe InterPro database (https://www.ebi.ac.uk/interpro/) provides an integrative classification of protein sequences into families, and identifies functionally important domains and conserved sites. InterProScan is the underlying software that allows protein and nucleic acid sequences to be searched against InterPro's signatures. Signatures are predictive models which describe protein families, domains or sites, and are provided by multiple databases. InterPro combines signatures representing equivalent families, domains or sites, and provides additional information such as descriptions, literature references and Gene Ontology (GO) terms, to produce a comprehensive resource for protein classification. Founded in 1999, InterPro has become one of the most widely used resources for protein family annotation. Here, we report the status of InterPro (version 81.0) in its 20th year of operation, and its associated software, including updates to database content, the release of a new website and REST API, and performance improvements in InterProScan.
664.
Macroscale patterns of oceanic zooplankton composition and size structure.
Brandão MC, Benedetti F, Martini S, Soviadan YD, Irisson JO, Romagnan JB, Elineau A, Desnos C, Jalabert L, Freire AS, Picheral M, Guidi L, Gorsky G, Bowler C, Karp-Boss L, Henry N, De Vargas C, Sullivan MB, Tara Oceans Consortium Coordinators , Stemmann L, Lombard F, Acinas SG, Babin M, Bork P, Boss E, Bowler C, Cochrane G, De Vargas C, Gorsky G, Guidi L, Grimsley N, Hingamp P, Iudicone D, Jaillon O, Kandels S, Karp-Boss L, Karsenti E, Not F, Ogata H, Poulton N, Pesant S, Raes J, Sardet C, Speich S, Stemmann L, Sullivan MB, Sunagawa S, Wincker P
Abstract + PDFOcean plankton comprise organisms from viruses to fish larvae that are fundamental to ecosystem functioning and the provision of marine services such as fisheries and CO sequestration. The latter services are partly governed by variations in plankton community composition and the expression of traits such as body size at community-level. While community assembly has been thoroughly studied for the smaller end of the plankton size spectrum, the larger end comprises ectotherms that are often studied at the species, or group-level, rather than as communities. The body size of marine ectotherms decreases with temperature, but controls on community-level traits remain elusive, hindering the predictability of marine services provision. Here, we leverage Tara Oceans datasets to determine how zooplankton community composition and size structure varies with latitude, temperature and productivity-related covariates in the global surface ocean. Zooplankton abundance and median size decreased towards warmer and less productive environments, as a result of changes in copepod composition. However, some clades displayed the opposite relationships, which may be ascribed to alternative feeding strategies. Given that climate models predict increasingly warmed and stratified oceans, our findings suggest that zooplankton communities will shift towards smaller organisms which might weaken their contribution to the biological carbon pump.
663.
Author Correction: Macroscale patterns of oceanic zooplankton composition and size structure.
Brandão MC, Benedetti F, Martini S, Soviadan YD, Irisson JO, Romagnan JB, Elineau A, Desnos C, Jalabert L, Freire AS, Picheral M, Guidi L, Gorsky G, Bowler C, Karp-Boss L, Henry N, De Vargas C, Sullivan MB, Tara Oceans Consortium Coordinators , Stemmann L, Lombard F, Acinas SG, Babin M, Bork P, Boss E, Bowler C, Cochrane G, De Vargas C, Gorsky G, Guidi L, Grimsley N, Hingamp P, Iudicone D, Jaillon O, Kandels S, Karp-Boss L, Karsenti E, Not F, Ogata H, Poulton N, Pesant S, Raes J, Sardet C, Speich S, Stemmann L, Sullivan MB, Sunagawa S, Wincker P
PDF662.
Human and preclinical studies of the host-gut microbiome co-metabolite hippurate as a marker and mediator of metabolic health.
Brial F, Chilloux J, Nielsen T, Vieira-Silva S, Falony G, Andrikopoulos P, Olanipekun M, Hoyles L, Djouadi F, Neves AL, Rodriguez-Martinez A, Mouawad GI, Pons N, Forslund S, Le-Chatelier E, Le Lay A, Nicholson J, Hansen T, Hyötyläinen T, Clément K, Oresic M, Bork P, Ehrlich SD, Raes J, Pedersen OB, Gauguier D, Dumas ME
Abstract + PDFGut microbial products are involved in regulation of host metabolism. In human and experimental studies, we explored the potential role of hippurate, a hepatic phase 2 conjugation product of microbial benzoate, as a marker and mediator of metabolic health.
661.
eggNOG-mapper v2: Functional Annotation, Orthology Assignments, and Domain Prediction at the Metagenomic Scale.
2021 Dec 9; 38(12): 5825-5829. PubMed: 34597405.
Abstract + PDFEven though automated functional annotation of genes represents a fundamental step in most genomic and metagenomic workflows, it remains challenging at large scales. Here, we describe a major upgrade to eggNOG-mapper, a tool for functional annotation based on precomputed orthology assignments, now optimized for vast (meta)genomic data sets. Improvements in version 2 include a full update of both the genomes and functional databases to those from eggNOG v5, as well as several efficiency enhancements and new features. Most notably, eggNOG-mapper v2 now allows for: (i) de novo gene prediction from raw contigs, (ii) built-in pairwise orthology prediction, (iii) fast protein domain discovery, and (iv) automated GFF decoration. eggNOG-mapper v2 is available as a standalone tool or as an online service at http://eggnog-mapper.embl.de.
660.
Combinatorial, additive and dose-dependent drug-microbiome associations.
Forslund SK, Chakaroun R, Zimmermann-Kogadeeva M, Markó L, Aron-Wisnewsky J, Nielsen T, Moitinho-Silva L, Schmidt TSB, Falony G, Vieira-Silva S, Adriouch S, Alves RJ, Assmann K, Bastard JP, Birkner T, Caesar R, Chilloux J, Coelho LP, Fezeu L, Galleron N, Helft G, Isnard R, Ji B, Kuhn M, Le Chatelier E, Myridakis A, Olsson L, Pons N, Prifti E, Quinquis B, Roume H, Salem JE, Sokolovska N, Tremaroli V, Valles-Colomer M, Lewinter C, Søndertoft NB, Pedersen HK, Hansen TH, MetaCardis Consortium , Gøtze JP, Køber L, Vestergaard H, Hansen T, Zucker JD, Hercberg S, Oppert JM, Letunic I, Nielsen J, Bäckhed F, Ehrlich SD, Dumas ME, Raes J, Pedersen O, Clément K, Stumvoll M, Bork P
Abstract + PDFDuring the transition from a healthy state to cardiometabolic disease, patients become heavily medicated, which leads to an increasingly aberrant gut microbiome and serum metabolome, and complicates biomarker discovery. Here, through integrated multi-omics analyses of 2,173 European residents from the MetaCardis cohort, we show that the explanatory power of drugs for the variability in both host and gut microbiome features exceeds that of disease. We quantify inferred effects of single medications, their combinations as well as additive effects, and show that the latter shift the metabolome and microbiome towards a healthier state, exemplified in synergistic reduction in serum atherogenic lipoproteins by statins combined with aspirin, or enrichment of intestinal Roseburia by diuretic agents combined with beta-blockers. Several antibiotics exhibit a quantitative relationship between the number of courses prescribed and progression towards a microbiome state that is associated with the severity of cardiometabolic disease. We also report a relationship between cardiometabolic drug dosage, improvement in clinical markers and microbiome composition, supporting direct drug effects. Taken together, our computational framework and resulting resources enable the disentanglement of the effects of drugs and disease on host and microbiome features in multimedicated individuals. Furthermore, the robust signatures identified using our framework provide new hypotheses for drug-host-microbiome interactions in cardiometabolic disease.
659.
Recurrent Frameshift Neoantigen Vaccine Elicits Protective Immunity With Reduced Tumor Burden and Improved Overall Survival in a Lynch Syndrome Mouse Model.
Gebert J, Gelincik O, Oezcan-Wahlbrink M, Marshall JD, Hernandez-Sanchez A, Urban K, Long M, Cortes E, Tosti E, Katzenmaier EM, Song Y, Elsaadi A, Deng N, Vilar E, Fuchs V, Nelius N, Yuan YP, Ahadova A, Sei S, Shoemaker RH, Umar A, Wei L, Liu S, Bork P, Edelmann W, von Knebel Doeberitz M, Lipkin SM, Kloor M
2021 Oct 2; 161(4): 1288-1302.e13. PubMed: 34224739.
Abstract + PDFDNA mismatch repair deficiency drives microsatellite instability (MSI). Cells with MSI accumulate numerous frameshift mutations. Frameshift mutations affecting cancer-related genes may promote tumorigenesis and, therefore, are shared among independently arising MSI tumors. Consequently, such recurrent frameshift mutations can give rise to shared immunogenic frameshift peptides (FSPs) that represent ideal candidates for a vaccine against MSI cancer. Pathogenic germline variants of mismatch repair genes cause Lynch syndrome (LS), a hereditary cancer syndrome affecting approximately 20-25 million individuals worldwide. Individuals with LS are at high risk of developing MSI cancer. Previously, we demonstrated safety and immunogenicity of an FSP-based vaccine in a phase I/IIa clinical trial in patients with a history of MSI colorectal cancer. However, the cancer-preventive effect of FSP vaccination in the scenario of LS has not yet been demonstrated.
658.
OGEE v3: Online GEne Essentiality database with increased coverage of organisms and human cell lines.
Gurumayum S, Jiang P, Hao X, Campos TL, Young ND, Korhonen PK, Gasser RB, Bork P, Zhao XM, He LJ, Chen WH
2021 Jan 8; 49(D1): D998-D1003. PubMed: 33084874.
Abstract + PDFOGEE is an Online GEne Essentiality database. Gene essentiality is not a static and binary property, rather a context-dependent and evolvable property in all forms of life. In OGEE we collect not only experimentally tested essential and non-essential genes, but also associated gene properties that contributes to gene essentiality. We tagged conditionally essential genes that show variable essentiality statuses across datasets to highlight complex interplays between gene functions and environmental/experimental perturbations. OGEE v3 contains gene essentiality datasets for 91 species; almost doubled from 48 species in previous version. To accommodate recent advances on human cancer essential genes (as known as tumor dependency genes) that could serve as targets for cancer treatment and/or drug development, we expanded the collection of human essential genes from 16 cell lines in previous to 581. These human cancer cell lines were tested with high-throughput experiments such as CRISPR-Cas9 and RNAi; in total, 150 of which were tested by both techniques. We also included factors known to contribute to gene essentiality for these cell lines, such as genomic mutation, methylation and gene expression, along with extensive graphical visualizations for ease of understanding of these factors. OGEE v3 can be accessible freely at https://v3.ogee.info.
657.
Dispersal strategies shape persistence and evolution of human gut bacteria.
Hildebrand F, Gossmann TI, Frioux C, Özkurt E, Myers PN, Ferretti P, Kuhn M, Bahram M, Nielsen HB, Bork P
2021 Jul 14; 29(7): 1167-1176.e9. PubMed: 34111423.
Abstract + PDFHuman gut bacterial strains can co-exist with their hosts for decades, but little is known about how these microbes persist and disperse, and evolve thereby. Here, we examined these processes in 5,278 adult and infant fecal metagenomes, longitudinally sampled in individuals and families. Our analyses revealed that a subset of gut species is extremely persistent in individuals, families, and geographic regions, represented often by locally successful strains of the phylum Bacteroidota. These "tenacious" bacteria show high levels of genetic adaptation to the human host but a high probability of loss upon antibiotic interventions. By contrast, heredipersistent bacteria, notably Firmicutes, often rely on dispersal strategies with weak phylogeographic patterns but strong family transmissions, likely related to sporulation. These analyses describe how different dispersal strategies can lead to the long-term persistence of human gut microbes with implications for gut flora modulations.
656.
Bioaccumulation of therapeutic drugs by human gut bacteria.
Klünemann M, Andrejev S, Blasche S, Mateus A, Phapale P, Devendran S, Vappiani J, Simon B, Scott TA, Kafkia E, Konstantinidis D, Zirngibl K, Mastrorilli E, Banzhaf M, Mackmull MT, Hövelmann F, Nesme L, Brochado AR, Maier L, Bock T, Periwal V, Kumar M, Kim Y, Tramontano M, Schultz C, Beck M, Hennig J, Zimmermann M, Sévin DC, Cabreiro F, Savitski MM, Bork P, Typas A, Patil KR
Abstract + PDFBacteria in the gut can modulate the availability and efficacy of therapeutic drugs. However, the systematic mapping of the interactions between drugs and bacteria has only started recently and the main underlying mechanism proposed is the chemical transformation of drugs by microorganisms (biotransformation). Here we investigated the depletion of 15 structurally diverse drugs by 25 representative strains of gut bacteria. This revealed 70 bacteria-drug interactions, 29 of which had not to our knowledge been reported before. Over half of the new interactions can be ascribed to bioaccumulation; that is, bacteria storing the drug intracellularly without chemically modifying it, and in most cases without the growth of the bacteria being affected. As a case in point, we studied the molecular basis of bioaccumulation of the widely used antidepressant duloxetine by using click chemistry, thermal proteome profiling and metabolomics. We find that duloxetine binds to several metabolic enzymes and changes the metabolite secretion of the respective bacteria. When tested in a defined microbial community of accumulators and non-accumulators, duloxetine markedly altered the composition of the community through metabolic cross-feeding. We further validated our findings in an animal model, showing that bioaccumulating bacteria attenuate the behavioural response of Caenorhabditis elegans to duloxetine. Together, our results show that bioaccumulation by gut bacteria may be a common mechanism that alters drug availability and bacterial metabolism, with implications for microbiota composition, pharmacokinetics, side effects and drug responses, probably in an individual manner.
655.
Early IFN-α signatures and persistent dysfunction are distinguishing features of NK cells in severe COVID-19.
Krämer B, Knoll R, Bonaguro L, ToVinh M, Raabe J, Astaburuaga-García R, Schulte-Schrepping J, Kaiser KM, Rieke GJ, Bischoff J, Monin MB, Hoffmeister C, Schlabe S, De Domenico E, Reusch N, Händler K, Reynolds G, Blüthgen N, Hack G, Finnemann C, Nischalke HD, Strassburg CP, Stephenson E, Su Y, Gardner L, Yuan D, Chen D, Goldman J, Rosenstiel P, Schmidt SV, Latz E, Hrusovsky K, Ball AJ, Johnson JM, Koenig PA, Schmidt FI, Haniffa M, Heath JR, Kümmerer BM, Keitel V, Jensen B, Stubbemann P, Kurth F, Sander LE, Sawitzki B, Deutsche COVID-19 OMICS Initiative (DeCOI) , Altmüller J, Angelov A, Bals R, Bartholomäus A, Becker A, Bitzer M, Bonifacio E, Bork P, Casadei N, Clavel T, Colome-Tatche M, Diefenbach A, Dilthey A, Fischer N, Förstner K, Franzenburg S, Frick JS, Gabernet G, Gagneur J, Ganzenmüller T, Göpel S, Goesmann A, Hain T, Heimbach A, Hummel M, Iftner A, Iftner T, Janssen S, Kalinowski J, Kallies R, Kehr B, Keller A, Kim-Hellmuth S, Klein C, Kohlbacher O, Köhrer K, Korbel J, Kühnert D, Kurth I, Landthaler M, Li Y, Ludwig K, Makarewicz O, Marz M, McHardy A, Mertes C, Nöthen M, Nürnberg P, Ohler U, Ossowski S, Overmann J, Pfeffer K, Poetsch AR, Pühler A, Rajewsky N, Ralser M, Rieß O, Ripke S, Nunes da Rocha U, Rosenstiel P, Saliba AE, Sander LE, Sawitzki B, Schiffer P, Schneider W, Schulte EC, Schultze JL, Sczyrba A, Singh Y, Sonnabend M, Stegle O, Stoye J, Theis F, Vehreschild J, Vogel J, von Kleist M, Walker A, Walter J, Wieczorek D, Winkler S, Ziebuhr J, Aschenbrenner AC, Schultze JL, Nattermann J
Abstract + PDFLongitudinal analyses of the innate immune system, including the earliest time points, are essential to understand the immunopathogenesis and clinical course of coronavirus disease (COVID-19). Here, we performed a detailed characterization of natural killer (NK) cells in 205 patients (403 samples; days 2 to 41 after symptom onset) from four independent cohorts using single-cell transcriptomics and proteomics together with functional studies. We found elevated interferon (IFN)-α plasma levels in early severe COVD-19 alongside increased NK cell expression of IFN-stimulated genes (ISGs) and genes involved in IFN-α signaling, while upregulation of tumor necrosis factor (TNF)-induced genes was observed in moderate diseases. NK cells exert anti-SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) activity but are functionally impaired in severe COVID-19. Further, NK cell dysfunction may be relevant for the development of fibrotic lung disease in severe COVID-19, as NK cells exhibited impaired anti-fibrotic activity. Our study indicates preferential IFN-α and TNF responses in severe and moderate COVID-19, respectively, and associates a prolonged IFN-α-induced NK cell response with poorer disease outcome.
654.
Interactive Tree Of Life (iTOL) v5: an online tool for phylogenetic tree display and annotation.
Letunic I, Bork P
2021 Jul 2; 49(W1): W293-W296. PubMed: 33885785.
Abstract + PDFThe Interactive Tree Of Life (https://itol.embl.de) is an online tool for the display, manipulation and annotation of phylogenetic and other trees. It is freely available and open to everyone. iTOL version 5 introduces a completely new tree display engine, together with numerous new features. For example, a new dataset type has been added (MEME motifs), while annotation options have been expanded for several existing ones. Node metadata display options have been extended and now also support non-numerical categorical values, as well as multiple values per node. Direct manual annotation is now available, providing a set of basic drawing and labeling tools, allowing users to draw shapes, labels and other features by hand directly onto the trees. Support for tree and dataset scales has been extended, providing fine control over line and label styles. Unrooted tree displays can now use the equal-daylight algorithm, proving a much greater display clarity. The user account system has been streamlined and expanded with new navigation options and currently handles >1 million trees from >70 000 individual users.
653.
SMART: recent updates, new developments and status in 2020.
2021 Jan 8; 49(D1): D458-D460. PubMed: 33104802.
Abstract + PDFSMART (Simple Modular Architecture Research Tool) is a web resource (https://smart.embl.de) for the identification and annotation of protein domains and the analysis of protein domain architectures. SMART version 9 contains manually curated models for more than 1300 protein domains, with a topical set of 68 new models added since our last update article (1). All the new models are for diverse recombinase families and subfamilies and as a set they provide a comprehensive overview of mobile element recombinases namely transposase, integrase, relaxase, resolvase, cas1 casposase and Xer like cellular recombinase. Further updates include the synchronization of the underlying protein databases with UniProt (2), Ensembl (3) and STRING (4), greatly increasing the total number of annotated domains and other protein features available in architecture analysis mode. Furthermore, SMART's vector-based protein display engine has been extended and updated to use the latest web technologies and the domain architecture analysis components have been optimized to handle the increased number of protein features available.
652.
Coupling proteomics and metabolomics for the unsupervised identification of protein-metabolite interactions in Chaetomium thermophilum.
Li YY, Kuhn M, Zukowska-Kasprzyk J, Hennrich ML, Kastritis PL, O'Reilly FJ, Phapale P, Beck M, Gavin AC, Bork P
Abstract + PDFProtein-metabolite interactions play an important role in the cell's metabolism and many methods have been developed to screen them in vitro. However, few methods can be applied at a large scale and not alter biological state. Here we describe a proteometabolomic approach, using chromatography to generate cell fractions which are then analyzed with mass spectrometry for both protein and metabolite identification. Integrating the proteomic and metabolomic analyses makes it possible to identify protein-bound metabolites. Applying the concept to the thermophilic fungus Chaetomium thermophilum, we predict 461 likely protein-metabolite interactions, most of them novel. As a proof of principle, we experimentally validate a predicted interaction between the ribosome and isopentenyl adenine.
651.
Polarization of microbial communities between competitive and cooperative metabolism.
Machado D, Maistrenko OM, Andrejev S, Kim Y, Bork P, Patil KR, Patil KR
2021 Feb; 5(2): 195-203. PubMed: 33398106.
Abstract + PDFResource competition and metabolic cross-feeding are among the main drivers of microbial community assembly. Yet the degree to which these two conflicting forces are reflected in the composition of natural communities has not been systematically investigated. Here, we use genome-scale metabolic modelling to assess the potential for resource competition and metabolic cooperation in large co-occurring groups (up to 40 members) across thousands of habitats. Our analysis reveals two distinct community types, which are clustered at opposite ends of a spectrum in a trade-off between competition and cooperation. At one end are highly cooperative communities, characterized by smaller genomes and multiple auxotrophies. At the other end are highly competitive communities, which feature larger genomes and overlapping nutritional requirements, and harbour more genes related to antimicrobial activity. The latter are mainly present in soils, whereas the former are found in both free-living and host-associated habitats. Community-scale flux simulations show that, whereas competitive communities can better resist species invasion but not nutrient shift, cooperative communities are susceptible to species invasion but resilient to nutrient change. We also show, by analysing an additional data set, that colonization by probiotic species is positively associated with the presence of cooperative species in the recipient microbiome. Together, our results highlight the bifurcation between competitive and cooperative metabolism in the assembly of natural communities and its implications for community modulation.
650.
Unravelling the collateral damage of antibiotics on gut bacteria.
Maier L, Goemans CV, Wirbel J, Kuhn M, Eberl C, Pruteanu M, Müller P, Garcia-Santamarina S, Cacace E, Zhang B, Gekeler C, Banerjee T, Anderson EE, Milanese A, Löber U, Forslund SK, Patil KR, Zimmermann M, Stecher B, Zeller G, Bork P, Typas A
Abstract + PDFAntibiotics are used to fight pathogens but also target commensal bacteria, disturbing the composition of gut microbiota and causing dysbiosis and disease. Despite this well-known collateral damage, the activity spectrum of different antibiotic classes on gut bacteria remains poorly characterized. Here we characterize further 144 antibiotics from a previous screen of more than 1,000 drugs on 38 representative human gut microbiome species. Antibiotic classes exhibited distinct inhibition spectra, including generation dependence for quinolones and phylogeny independence for β-lactams. Macrolides and tetracyclines, both prototypic bacteriostatic protein synthesis inhibitors, inhibited nearly all commensals tested but also killed several species. Killed bacteria were more readily eliminated from in vitro communities than those inhibited. This species-specific killing activity challenges the long-standing distinction between bactericidal and bacteriostatic antibiotic classes and provides a possible explanation for the strong effect of macrolides on animal and human gut microbiomes. To mitigate this collateral damage of macrolides and tetracyclines, we screened for drugs that specifically antagonized the antibiotic activity against abundant Bacteroides species but not against relevant pathogens. Such antidotes selectively protected Bacteroides species from erythromycin treatment in human-stool-derived communities and gnotobiotic mice. These findings illluminate the activity spectra of antibiotics in commensal bacteria and suggest strategies to circumvent their adverse effects on the gut microbiota.
649.
Profiling cellular diversity in sponges informs animal cell type and nervous system evolution.
Musser JM, Schippers KJ, Nickel M, Mizzon G, Kohn AB, Pape C, Ronchi P, Papadopoulos N, Tarashansky AJ, Hammel JU, Wolf F, Liang C, Hernández-Plaza A, Cantalapiedra CP, Achim K, Schieber NL, Pan L, Ruperti F, Francis WR, Vargas S, Kling S, Renkert M, Polikarpov M, Bourenkov G, Feuda R, Gaspar I, Burkhardt P, Wang B, Bork P, Beck M, Schneider TR, Kreshuk A, Wörheide G, Huerta-Cepas J, Schwab Y, Moroz LL, Arendt D
Abstract + PDFThe evolutionary origin of metazoan cell types such as neurons and muscles is not known. Using whole-body single-cell RNA sequencing in a sponge, an animal without nervous system and musculature, we identified 18 distinct cell types. These include nitric oxide–sensitive contractile pinacocytes, amoeboid phagocytes, and secretory neuroid cells that reside in close contact with digestive choanocytes that express scaffolding and receptor proteins. Visualizing neuroid cells by correlative x-ray and electron microscopy revealed secretory vesicles and cellular projections enwrapping choanocyte microvilli and cilia. Our data show a communication system that is organized around sponge digestive chambers, using conserved modules that became incorporated into the pre- and postsynapse in the nervous systems of other animals.
648.
GUNC: detection of chimerism and contamination in prokaryotic genomes.
2021 Jun 13; 22(1): 178. PubMed: 34120611.
Abstract + PDFGenomes are critical units in microbiology, yet ascertaining quality in prokaryotic genome assemblies remains a formidable challenge. We present GUNC (the Genome UNClutterer), a tool that accurately detects and quantifies genome chimerism based on the lineage homogeneity of individual contigs using a genome's full complement of genes. GUNC complements existing approaches by targeting previously underdetected types of contamination: we conservatively estimate that 5.7% of genomes in GenBank, 5.2% in RefSeq, and 15-30% of pre-filtered "high-quality" metagenome-assembled genomes in recent studies are undetected chimeras. GUNC provides a fast and robust tool to substantially improve prokaryotic genome quality.
647.
Prognostic performance of 7 biomarkers compared to liver biopsy in early alcohol-related liver disease.
Rasmussen DN, Thiele M, Johansen S, Kjærrgaard M, Lindvig KP, Israelsen M, Antonsen S, Detlefsen S, Krag A, GALAXY , MicrobLiver consortia , Anastasiadou E, Arumugam M, Bork P, Hansen T, Hartoft C, Israelsen H, Karsdal M, Legido-Quigley C, Melberg HO, Thiele M, Trebicka J, Krag A, Bork P, Mann M, Matthijnssens J, Krag A, Hansen T
Abstract + PDFAlcohol is the most common cause of liver-related mortality and morbidity. We therefore aimed to assess and compare the prognostic performance of elastography and blood-based markers to predict time to the first liver-related event, severe infection, and all-cause mortality in patients with a history of excess drinking.
646.
Compendium of 530 metagenome-assembled bacterial and archaeal genomes from the polar Arctic Ocean.
Royo-Llonch M, Sánchez P, Ruiz-González C, Salazar G, Pedrós-Alió C, Sebastián M, Labadie K, Paoli L, M Ibarbalz F, Zinger L, Churcheward B, Tara Oceans coordinators , Chaffron S, Eveillard D, Karsenti E, Sunagawa S, Wincker P, Karp-Boss L, Bowler C, Acinas SG, Babin M, Bork P, Boss E, Cochrane G, De Vargas C, Gorsky G, Grimsley N, Guidi L, Hingamp P, Iudicone D, Jaillon O, Kandels S, Not F, Ogata H, Pesant S, Poulton N, Raes J, Sardet C, Speich S, Setmmann L, Sullivan MB
2021 12; 6(12): 1561-1574. PubMed: 34782724.
Abstract + PDFThe role of the Arctic Ocean ecosystem in climate regulation may depend on the responses of marine microorganisms to environmental change. We applied genome-resolved metagenomics to 41 Arctic seawater samples, collected at various depths in different seasons during the Tara Oceans Polar Circle expedition, to evaluate the ecology, metabolic potential and activity of resident bacteria and archaea. We assembled 530 metagenome-assembled genomes (MAGs) to form the Arctic MAGs catalogue comprising 526 species. A total of 441 MAGs belonged to species that have not previously been reported and 299 genomes showed an exclusively polar distribution. Most Arctic MAGs have large genomes and the potential for fast generation times, both of which may enable adaptation to a copiotrophic lifestyle in nutrient-rich waters. We identified 38 habitat generalists and 111 specialists in the Arctic Ocean. We also found a general prevalence of 14 mixotrophs, while chemolithoautotrophs were mostly present in the mesopelagic layer during spring and autumn. We revealed 62 MAGs classified as key Arctic species, found only in the Arctic Ocean, showing the highest gene expression values and predicted to have habitat-specific traits. The Artic MAGs catalogue will inform our understanding of polar microorganisms that drive global biogeochemical cycles.
645.
A 12-genus bacterial signature identifies a group of severe autistic children with differential sensory behavior and brain structures.
Shi K, Zhang L, Yu J, Chen Z, Lai S, Zhao X, Li WG, Luo Q, Lin W, Feng J, Bork P, Zhao XM, Li F
2021 Feb; 11(2): e314. PubMed: 33634969.
PDF644.
SARS-CoV-2 infection paralyzes cytotoxic and metabolic functions of the immune cells.
Singh Y, Trautwein C, Fendel R, Krickeberg N, Berezhnoy G, Bissinger R, Ossowski S, Salker MS, Casadei N, Riess O, Deutsche COVID-19 OMICS Initiate (DeCOI) , Altmüller J, Angelov A, Aschenbrenner AC, Bals R, Bartholomäus A, Becker A, Becker M, Bezdan D, Bitzer M, Blumert C, Bonifacio E, Bork P, Boyke B, Blum H, Casadei N, Clavel T, Colome-Tatche M, Cornberg M, Velázquez IADLR, Diefenbach A, Dilthey A, Fischer N, Förstner K, Franzenburg S, Frick JS, Gabernet G, Gagneur J, Ganzenmueller T, Gauder M, Geißert J, Goesmann A, Göpel S, Grundhoff A, Grundmann H, Hain T, Hanses F, Hehr U, Heimbach A, Hoeper M, Horn F, Hübschmann D, Hummel M, Iftner T, Iftner A, Illig T, Janssen S, Kalinowski J, Kallies R, Kehr B, Keller A, Keppler OT, Kim-Hellmuth S, Klein C, Knop M, Kohlbacher O, Köhrer K, Korbel JO, Kremsner PG, Kühnert D, Kurth I, Landthaler M, Li Y, Ludwig KU, Makarewicz O, Marz M, McHardy AC, Mertes C, Münchhoff M, Nahnsen S, Nöthen M, Ntoumi F, Nürnberg P, Ossowski S, Overmann J, Peter S, Pfeffer K, Pink I, Poetsch AR, Protzer U, Pühler A, Rajewsky N, Ralser M, Reiche K, Rieß O, Ripke S, da Rocha UN, Rosenstiel P, Saliba AE, Sander LE, Sawitzki B, Scheithauer S, Schiffer P, Schmid-Burgk J, Schneider W, Schulte EC, Schultze JL, Sczyrba A, Sharaf ML, Singh Y, Sonnabend M, Stegle O, Stoye J, Theis F, Ulas T, Vehreschild J, Velavan TP, Vogel J, Volland S, von Kleist M, Walker A, Walter J, Wieczorek D, Winkler S, Ziebuhr J.
Abstract + PDFThe SARS-CoV-2 virus is the causative agent of the global COVID-19 infectious disease outbreak, which can lead to acute respiratory distress syndrome (ARDS). However, it is still unclear how the virus interferes with immune cell and metabolic functions in the human body. In this study, we investigated the immune response in acute or convalescent COVID-19 patients. We characterized the peripheral blood mononuclear cells (PBMCs) using flow cytometry and found that CD8 T cells were significantly subsided in moderate COVID-19 and convalescent patients. Furthermore, characterization of CD8 T cells suggested that convalescent patients have significantly diminished expression of both perforin and granzyme A. Using H-NMR spectroscopy, we characterized the metabolic status of their autologous PBMCs. We found that fructose, lactate and taurine levels were elevated in infected (mild and moderate) patients compared with control and convalescent patients. Glucose, glutamate, formate and acetate levels were attenuated in COVID-19 (mild and moderate) patients. In summary, our report suggests that SARS-CoV-2 infection leads to disrupted CD8 T cytotoxic functions and changes the overall metabolic functions of immune cells.
643.
The STRING database in 2021: customizable protein-protein networks, and functional characterization of user-uploaded gene/measurement sets.
Szklarczyk D, Gable AL, Nastou KC, Lyon D, Kirsch R, Pyysalo S, Doncheva NT, Legeay M, Fang T, Bork P, Jensen LJ, von Mering C
2021 Jan 8; 49(D1): D605-D612. PubMed: 33237311.
Abstract + PDFCellular life depends on a complex web of functional associations between biomolecules. Among these associations, protein-protein interactions are particularly important due to their versatility, specificity and adaptability. The STRING database aims to integrate all known and predicted associations between proteins, including both physical interactions as well as functional associations. To achieve this, STRING collects and scores evidence from a number of sources: (i) automated text mining of the scientific literature, (ii) databases of interaction experiments and annotated complexes/pathways, (iii) computational interaction predictions from co-expression and from conserved genomic context and (iv) systematic transfers of interaction evidence from one organism to another. STRING aims for wide coverage; the upcoming version 11.5 of the resource will contain more than 14 000 organisms. In this update paper, we describe changes to the text-mining system, a new scoring-mode for physical interactions, as well as extensive user interface features for customizing, extending and sharing protein networks. In addition, we describe how to query STRING with genome-wide, experimental data, including the automated detection of enriched functionalities and potential biases in the user's query data. The STRING resource is available online, at https://string-db.org/.
642.
Correction to 'The STRING database in 2021: customizable protein-protein networks, and functional characterization of user-uploaded gene/measurement sets'.
Szklarczyk D, Gable AL, Nastou KC, Lyon D, Kirsch R, Pyysalo S, Doncheva NT, Legeay M, Fang T, Bork P, Jensen LJ, von Mering C
2021 Oct 11; 49(18): 10800. PubMed: 34530444.
PDF641.
Progressive alcohol-related liver fibrosis is characterised by imbalanced collagen formation and degradation.
Thiele M, Johansen S, Gudmann NS, Madsen B, Kjaergaard M, Nielsen MJ, Leeming DJ, Jacobsen S, Bendtsen F, Møller S, Detlefsen S, Karsdal M, Krag A, GALAXY consortium , Arumugam M, Bork P, Hansen T, Anastasiadou E, Hartoft C, Israelsen H, Legido-Quigley C, Melberg HO, Trebicka J
2021 10; 54(8): 1070-1080. PubMed: 34428307.
Abstract + PDFLiver fibrosis accumulation is considered a turnover disease, with formation exceeding degradation, although this hypothesis has never been tested in humans.
640.
Utilizing the gut microbiome in decompensated cirrhosis and acute-on-chronic liver failure.
Trebicka J, Bork P, Krag A, Arumugam M
2021 Mar; 18(3): 167-180. PubMed: 33257833.
Abstract + PDFThe human gut microbiome has emerged as a major player in human health and disease. The liver, as the first organ to encounter microbial products that cross the gut epithelial barrier, is affected by the gut microbiome in many ways. Thus, the gut microbiome might play a major part in the development of liver diseases. The common end stage of liver disease is decompensated cirrhosis and the further development towards acute-on-chronic liver failure (ACLF). These conditions have high short-term mortality. There is evidence that translocation of components of the gut microbiota, facilitated by different pathogenic mechanisms such as increased gut epithelial permeability and portal hypertension, is an important driver of decompensation by induction of systemic inflammation, and thereby also ACLF. Elucidating the role of the gut microbiome in the aetiology of decompensated cirrhosis and ACLF deserves further investigation and improvement; and might be the basis for development of diagnostic and therapeutic strategies. In this Review, we focus on the possible pathogenic, diagnostic and therapeutic role of the gut microbiome in decompensation of cirrhosis and progression to ACLF.
639.
A Previously Undescribed Highly Prevalent Phage Identified in a Danish Enteric Virome Catalog.
Van Espen L, Bak EG, Beller L, Close L, Deboutte W, Juel HB, Nielsen T, Sinar D, De Coninck L, Frithioff-Bøjsøe C, Fonvig CE, Jacobsen S, Kjærgaard M, Thiele M, Fullam A, Kuhn M, Holm JC, Bork P, Krag A, Hansen T, Arumugam M, Matthijnssens J
Abstract + PDFGut viruses are important, yet often neglected, players in the complex human gut microbial ecosystem. Recently, the number of human gut virome studies has been increasing; however, we are still only scratching the surface of the immense viral diversity. In this study, 254 virus-enriched fecal metagenomes from 204 Danish subjects were used to generate the anish nteric irme atalog (DEVoC) containing 12,986 nonredundant viral scaffolds, of which the majority was previously undescribed, encoding 190,029 viral genes. The DEVoC was used to compare 91 healthy DEVoC gut viromes from children, adolescents, and adults that were used to create the DEVoC. Gut viromes of healthy Danish subjects were dominated by phages. While most phage genomes (PGs) only occurred in a single subject, indicating large virome individuality, 39 PGs were present in more than 10 healthy subjects. Among these 39 PGs, the prevalences of three PGs were associated with age. To further study the prevalence of these 39 prevalent PGs, 1,880 gut virome data sets of 27 studies from across the world were screened, revealing several age-, geography-, and disease-related prevalence patterns. Two PGs also showed a remarkably high prevalence worldwide-a crAss-like phage (20.6% prevalence), belonging to the tentative subfamily, and a previously undescribed circular temperate phage infecting Bacteroides dorei (14.4% prevalence), called LoVEphage because it encodes ots f iral lements. Due to the LoVEphage's high prevalence and novelty, public data sets in which the LoVEphage was detected were assembled, resulting in an additional 18 circular LoVEphage-like genomes (67.9 to 72.4 kb). Through generation of the DEVoC, we added numerous previously uncharacterized viral genomes and genes to the ever-increasing worldwide pool of human gut viromes. The DEVoC, the largest human gut virome catalog generated from consistently processed fecal samples, facilitated the analysis of the 91 healthy Danish gut viromes. Characterizing the biggest cohort of healthy gut viromes from children, adolescents, and adults to date confirmed the previously established high interindividual variation in human gut viromes and demonstrated that the effect of age on the gut virome composition was limited to the prevalence of specific phage (groups). The identification of a previously undescribed prevalent phage illustrates the usefulness of developing virome catalogs, and we foresee that the DEVoC will benefit future analysis of the roles of gut viruses in human health and disease.
638.
Characterization of SARS-CoV-2 infection clusters based on integrated genomic surveillance, outbreak analysis and contact tracing in an urban setting.
Walker A, Houwaart T, Finzer P, Ehlkes L, Tyshaieva A, Damagnez M, Strelow D, Duplessis A, Nicolai J, Wienemann T, Tamayo T, Kohns Vasconcelos M, Hülse L, Hoffmann K, Lübke N, Hauka S, Andree M, Däumer MP, Thielen A, Kolbe-Busch S, Göbels K, Zotz R, Pfeffer K, Timm J, Dilthey AT, German COVID-19 Omics Initiative (DeCOI) , Altmüller J, Angelov A, Aschenbrenner AC, Bals R, Bartholomäus A, Becker A, Bezdan D, Bitzer M, Blum H, Bonifacio E, Bork P, Casadei N, Clavel T, Colome-Tatche M, Velázquez IADLR, Diefenbach A, Dilthey A, Fischer N, Förstner K, Franzenburg S, Frick JS, Gabernet G, Gagneur J, Ganzenmüller T, Gauder M, Goesmann A, Göpel S, Grundhoff A, Grundmann H, Hain T, Heimbach A, Hummel M, Iftner T, Iftner A, Janssen S, Kalinowski J, Kallies R, Kehr B, Keller A, Keppler O, Kim-Hellmuth S, Klein C, Knop M, Kohlbacher O, Köhrer K, Korbel JO, Kremsner PG, Kühnert D, Kurth I, Landthaler M, Li Y, Ludwig K, Makarewicz O, Marz M, McHardy A, Mertes C, Münchhoff M, Nahnsen S, Nöthen M, Ntoumi F, Nürnberg P, Ohler U, Ossowski S, Overmann J, Peter S, Pfeffer K, Poetsch AR, Protzer U, Pühler A, Rajewsky N, Ralser M, Rieß O, Ripke S, Rocha U, Rosenstiel P, Saliba E, Sander LE, Sawitzki B, Scheithauer S, Schiffer P, Schmid-Burgk J, Schneider W, Schulte EC, Schultze J, Sczyrba A, Sharaf ML, Singh Y, Sonnabend M, Stegle O, Stoye J, Theis F, Vehreschild J, Velavan TP, Vogel J, von Kleist M, Walker A, Walter J, Wieczorek D, Winkler S, Ziebuhr J.
2021 Jun 28; [Epub ahead of print] PubMed: 34181711.
Abstract + PDFTracing of SARS-CoV-2 transmission chains is still a major challenge for public health authorities, when incidental contacts are not recalled or are not perceived as potential risk contacts. Viral sequencing can address key questions about SARS-CoV-2 evolution and may support reconstruction of viral transmission networks by integration of molecular epidemiology into classical contact tracing.
637.
Swarm Learning for decentralized and confidential clinical machine learning.
Warnat-Herresthal S, Schultze H, Shastry KL, Manamohan S, Mukherjee S, Garg V, Sarveswara R, Händler K, Pickkers P, Aziz NA, Ktena S, Tran F, Bitzer M, Ossowski S, Casadei N, Herr C, Petersheim D, Behrends U, Kern F, Fehlmann T, Schommers P, Lehmann C, Augustin M, Rybniker J, Altmüller J, Mishra N, Bernardes JP, Krämer B, Bonaguro L, Schulte-Schrepping J, De Domenico E, Siever C, Kraut M, Desai M, Monnet B, Saridaki M, Siegel CM, Drews A, Nuesch-Germano M, Theis H, Heyckendorf J, Schreiber S, Kim-Hellmuth S, COVID-19 Aachen Study (COVAS) , Nattermann J, Skowasch D, Kurth I, Keller A, Bals R, Nürnberg P, Rieß O, Rosenstiel P, Netea MG, Theis F, Mukherjee S, Backes M, Aschenbrenner AC, Ulas T, Deutsche COVID-19 OMICS Initiative (DeCOI) , Breteler MMB, Giamarellos-Bourboulis EJ, Kox M, Becker M, Cheran S, Woodacre MS, Goh EL, Schultze JL, Balfanz P, Eggermann T, Boor P, Hausmann R, Kuhn H, Isfort S, Stingl JC, Schmalzing G, Kuhl CK, Röhrig R, Marx G, Uhlig S, Dahl E, Müller-Wieland D, Dreher M, Marx N, Angelov A, Bartholomäus A, Becker A, Bezdan D, Blumert C, Bonifacio E, Bork P, Boyke B, Blum H, Clavel T, Colome-Tatche M, Cornberg M, Velázquez IADL, Diefenbach A, Dilthey A, Fischer N, Förstner K, Franzenburg S, Frick JS, Gabernet G, Gagneur J, Ganzenmueller T, Gauder M, Geißert J, Goesmann A, Göpel S, Grundhoff A, Grundmann H, Hain T, Hanses F, Hehr U, Heimbach A, Hoeper M, Horn F, Hübschmann D, Hummel M, Iftner T, Iftner A, Illig T, Janssen S, Kalinowski J, Kallies R, Kehr B, Keppler OT, Klein C, Knop M, Kohlbacher O, Köhrer K, Korbel J, Kremsner PG, Kühnert D, Landthaler M, Li Y, Ludwig KU, Makarewicz O, Marz M, McHardy AC, Mertes C, Münchhoff M, Nahnsen S, Nöthen M, Ntoumi F, Overmann J, Peter S, Pfeffer K, Pink I, Poetsch AR, Protzer U, Pühler A, Rajewsky N, Ralser M, Reiche K, Ripke S, da Rocha UN, Saliba AE, Sander LE, Sawitzki B, Scheithauer S, Schiffer P, Schmid-Burgk J, Schneider W, Schulte EC, Sczyrba A, Sharaf ML, Singh Y, Sonnabend M, Stegle O, Stoye J, Vehreschild J, Velavan TP, Vogel J, Volland S, von Kleist M, Walker A, Walter J, Wieczorek D, Winkler S, Ziebuhr J
Abstract + PDFFast and reliable detection of patients with severe and heterogeneous illnesses is a major goal of precision medicine. Patients with leukaemia can be identified using machine learning on the basis of their blood transcriptomes. However, there is an increasing divide between what is technically possible and what is allowed, because of privacy legislation. Here, to facilitate the integration of any medical data from any data owner worldwide without violating privacy laws, we introduce Swarm Learning-a decentralized machine-learning approach that unites edge computing, blockchain-based peer-to-peer networking and coordination while maintaining confidentiality without the need for a central coordinator, thereby going beyond federated learning. To illustrate the feasibility of using Swarm Learning to develop disease classifiers using distributed data, we chose four use cases of heterogeneous diseases (COVID-19, tuberculosis, leukaemia and lung pathologies). With more than 16,400 blood transcriptomes derived from 127 clinical studies with non-uniform distributions of cases and controls and substantial study biases, as well as more than 95,000 chest X-ray images, we show that Swarm Learning classifiers outperform those developed at individual sites. In addition, Swarm Learning completely fulfils local confidentiality regulations by design. We believe that this approach will notably accelerate the introduction of precision medicine.
636.
Microbiome meta-analysis and cross-disease comparison enabled by the SIAMCAT machine learning toolbox.
2021 Mar 30; 22(1): 93. PubMed: 33785070.
Abstract + PDFThe human microbiome is increasingly mined for diagnostic and therapeutic biomarkers using machine learning (ML). However, metagenomics-specific software is scarce, and overoptimistic evaluation and limited cross-study generalization are prevailing issues. To address these, we developed SIAMCAT, a versatile R toolbox for ML-based comparative metagenomics. We demonstrate its capabilities in a meta-analysis of fecal metagenomic studies (10,803 samples). When naively transferred across studies, ML models lost accuracy and disease specificity, which could however be resolved by a novel training set augmentation strategy. This reveals some biomarkers to be disease-specific, with others shared across multiple conditions. SIAMCAT is freely available from siamcat.embl.de .
2020 15 publication(s).
635.
Plant nutrient-acquisition strategies drive topsoil microbiome structure and function.
Bahram M, Netherway T, Hildebrand F, Pritsch K, Drenkhan R, Loit K, Anslan S, Bork P, Tedersoo L
2020 Aug 12; 227(4): 1189-1199. PubMed: 32279325.
Abstract + PDFPlant nutrient acquisition strategies drive soil processes and vegetation performance, but their effect on the soil microbiome remains poorly understood. This knowledge is important to predict the shifts in microbial diversity and functions to increasing changes in vegetation traits under global change. Here we documented the topsoil microbiomes of 145 boreal and temperate terrestrial sites in the Baltic region that broadly differed in vegetation type and nutritional traits, such as mycorrhizal types and symbiotic nitrogen-fixation. We found that sites dominated by arbuscular mycorrhizal (AM) vegetation harbor relatively more AM fungi, bacteria, fungal saprotrophs, and pathogens in the topsoil compared with sites dominated by ectomycorrhizal (EM) plants. These differences in microbiome composition reflect the rapid nutrient cycling and negative plant-soil feedback in AM soils. Lower fungal diversity and bacteria-to-fungi ratios in EM-dominated habitats are driven by monodominance of woody vegetation as well as soil acidification by EM fungi, which are associated with greater diversity and relative abundance of carbohydrate-active enzymes. Our study suggests that shifts in vegetation related to global change and land use may strongly alter the topsoil microbiome structure and function.
634.
Longitudinal Multi-omics Analyses Identify Responses of Megakaryocytes, Erythroid Cells, and Plasmablasts as Hallmarks of Severe COVID-19.
Bernardes JP, Mishra N, Tran F, Bahmer T, Best L, Blase JI, Bordoni D, Franzenburg J, Geisen U, Josephs-Spaulding J, Köhler P, Künstner A, Rosati E, Aschenbrenner AC, Bacher P, Baran N, Boysen T, Brandt B, Bruse N, Dörr J, Dräger A, Elke G, Ellinghaus D, Fischer J, Forster M, Franke A, Franzenburg S, Frey N, Friedrichs A, Fuß J, Glück A, Hamm J, Hinrichsen F, Hoeppner MP, Imm S, Junker R, Kaiser S, Kan YH, Knoll R, Lange C, Laue G, Lier C, Lindner M, Marinos G, Markewitz R, Nattermann J, Noth R, Pickkers P, Rabe KF, Renz A, Röcken C, Rupp J, Schaffarzyk A, Scheffold A, Schulte-Schrepping J, Schunk D, Skowasch D, Ulas T, Wandinger KP, Wittig M, Zimmermann J, Busch H, Hoyer BF, Kaleta C, Heyckendorf J, Kox M, Rybniker J, Schreiber S, Schultze JL, Rosenstiel P, HCA Lung Biological Network , Deutsche COVID-19 OMICS Initiative (DeCOI) , Banovich NE, Desai T, Eickelberg O, Haniffa M, Horvath P, Kropski JA, Lafyatis R, Lundeberg J, Meyer K, Nawijn MC, Nikolic M, Montanes JO, Pe’er D, Tata PR, Rawlins E, Regev A, Reyfman P, Samakovlis C, Schultze J, Shalek A, Shepherd D, Spence J, Teichmann S, Theis F, Tsankov A, van den Berge M, von Papen M, Whitsett J, Zaragosi LE, Angelov A, Bals R, Bartholomäus A, Becker A, Bezdan D, Bonifacio E, Bork P, Clavel T, Colme-Tatche M, Diefenbach A, Dilthey A, Fischer N, Förstner K, Frick JS, Gagneur J, Goesmann A, Hain T, Hummel M, Janssen S, Kalinowski J, Kallies R, Kehr B, Keller A, Kim-Hellmuth S, Klein C, Kohlbacher O, Korbel JO, Kurth I, Landthaler M, Li Y, Ludwig K, Makarewicz O, Marz M, McHardy A, Mertes C, Nöthen M, Nürnberg P, Ohler U, Ossowski S, Overmann J, Peter S, Pfeffer K, Poetsch AR, Pühler A, Rajewsky N, Ralser M, Rieß O, Ripke S, da Rocha UN, Saliba AE, Sander LE
Abstract + PDFTemporal resolution of cellular features associated with a severe COVID-19 disease trajectory is needed for understanding skewed immune responses and defining predictors of outcome. Here, we performed a longitudinal multi-omics study using a two-center cohort of 14 patients. We analyzed the bulk transcriptome, bulk DNA methylome, and single-cell transcriptome (>358,000 cells, including BCR profiles) of peripheral blood samples harvested from up to 5 time points. Validation was performed in two independent cohorts of COVID-19 patients. Severe COVID-19 was characterized by an increase of proliferating, metabolically hyperactive plasmablasts. Coinciding with critical illness, we also identified an expansion of interferon-activated circulating megakaryocytes and increased erythropoiesis with features of hypoxic signaling. Megakaryocyte- and erythroid-cell-derived co-expression modules were predictive of fatal disease outcome. The study demonstrates broad cellular effects of SARS-CoV-2 infection beyond adaptive immune cells and provides an entry point toward developing biomarkers and targeted treatments of patients with COVID-19.
633.
Towards standardisation of naming novel prokaryotic taxa in the age of high-throughput microbiology.
Hildebrand F, Pallen MJ, Bork P
PDF632.
Identification of metabolites from tandem mass spectra with a machine learning approach utilizing structural features.
2020 Feb 15; 36(4): 1213-1218. PubMed: 31605112.
Abstract + PDFUntargeted mass spectrometry is a powerful method for detecting metabolites in biological samples. However, fast and accurate identification of the metabolites' structures from MS/MS spectra is still a great challenge.
631.
Disentangling the impact of environmental and phylogenetic constraints on prokaryotic within-species diversity.
Maistrenko OM, Mende DR, Luetge M, Hildebrand F, Schmidt TSB, Li SS, Rodrigues JFM, von Mering C, Coelho LP, Huerta-Cepas J, Sunagawa S, Bork P
Abstract + PDFMicrobial organisms inhabit virtually all environments and encompass a vast biological diversity. The pangenome concept aims to facilitate an understanding of diversity within defined phylogenetic groups. Hence, pangenomes are increasingly used to characterize the strain diversity of prokaryotic species. To understand the interdependence of pangenome features (such as the number of core and accessory genes) and to study the impact of environmental and phylogenetic constraints on the evolution of conspecific strains, we computed pangenomes for 155 phylogenetically diverse species (from ten phyla) using 7,000 high-quality genomes to each of which the respective habitats were assigned. Species habitat ubiquity was associated with several pangenome features. In particular, core-genome size was more important for ubiquity than accessory genome size. In general, environmental preferences had a stronger impact on pangenome evolution than phylogenetic inertia. Environmental preferences explained up to 49% of the variance for pangenome features, compared with 18% by phylogenetic inertia. This observation was robust when the dataset was extended to 10,100 species (59 phyla). The importance of environmental preferences was further accentuated by convergent evolution of pangenome features in a given habitat type across different phylogenetic clades. For example, the soil environment promotes expansion of pangenome size, while host-associated habitats lead to its reduction. Taken together, we explored the global principles of pangenome evolution, quantified the influence of habitat, and phylogenetic inertia on the evolution of pangenomes and identified criteria governing species ubiquity and habitat specificity.
630.
proGenomes2: an improved database for accurate and consistent habitat, taxonomic and functional annotations of prokaryotic genomes.
Mende DR, Letunic I, Maistrenko OM, Schmidt TSB, Milanese A, Paoli L, Hernández-Plaza A, Orakov AN, Forslund SK, Sunagawa S, Zeller G, Huerta-Cepas J, Coelho LP, Bork P
2020 Jan 8; 48: D621-D625. PubMed: 31647096.
Abstract + PDFMicrobiology depends on the availability of annotated microbial genomes for many applications. Comparative genomics approaches have been a major advance, but consistent and accurate annotations of genomes can be hard to obtain. In addition, newer concepts such as the pan-genome concept are still being implemented to help answer biological questions. Hence, we present proGenomes2, which provides 87 920 high-quality genomes in a user-friendly and interactive manner. Genome sequences and annotations can be retrieved individually or by taxonomic clade. Every genome in the database has been assigned to a species cluster and most genomes could be accurately assigned to one or multiple habitats. In addition, general functional annotations and specific annotations of antibiotic resistance genes and single nucleotide variants are provided. In short, proGenomes2 provides threefold more genomes, enhanced habitat annotations, updated taxonomic and functional annotation and improved linkage to the NCBI BioSample database. The database is available at http://progenomes.embl.de/.
629.
(Phospho)proteomic Profiling of Microsatellite Unstable CRC Cells Reveals Alterations in Nuclear Signaling and Cholesterol Metabolism Caused by Frameshift Mutation of NMD Regulator UPF3A.
Michalak M, Katzenmaier EM, Roeckel N, Woerner SM, Fuchs V, Warnken U, Yuan YP, Bork P, Neu-Yilik G, Kulozik A, von Knebel Doeberitz M, Kloor M, Kopitz J, Gebert J
2020 Jul 23; 21(15): . PubMed: 32718059.
Abstract + PDFDNA mismatch repair-deficient colorectal cancers (CRCs) accumulate numerous frameshift mutations at repetitive sequences recognized as microsatellite instability (MSI). When coding mononucleotide repeats (cMNRs) are affected, tumors accumulate frameshift mutations and premature termination codons (PTC) potentially leading to truncated proteins. Nonsense-mediated RNA decay (NMD) can degrade PTC-containing transcripts and protect from such faulty proteins. As it also regulates normal transcripts and cellular physiology, we tested whether NMD genes themselves are targets of MSI frameshift mutations. A high frequency of cMNR frameshift mutations in the gene was found in MSI CRC cell lines (67.7%), MSI colorectal adenomas (55%) and carcinomas (63%). In normal colonic crypts, UPF3A expression was restricted to single chromogranin A-positive cells. SILAC-based proteomic analysis of KM12 CRC cells revealed UPF3A-dependent down-regulation of several enzymes involved in cholesterol biosynthesis. Furthermore, reconstituted UPF3A expression caused alterations of 85 phosphosites in 52 phosphoproteins. Most of them (38/52, 73%) reside in nuclear phosphoproteins involved in regulation of gene expression and RNA splicing. Since UPF3A mutations can modulate the (phospho)proteomic signature and expression of enzymes involved in cholesterol metabolism in CRC cells, UPF3A may influence other processes than NMD and loss of UPF3A expression might provide a growth advantage to MSI CRC cells.
628.
Author Correction: Imidazole propionate is increased in diabetes and associated with dietary patterns and altered microbial ecology.
Molinaro A, Bel Lassen P, Henricsson M, Wu H, Adriouch S, Belda E, Chakaroun R, Nielsen T, Bergh PO, Rouault C, André S, Marquet F, Andreelli F, Salem JE, Assmann K, Bastard JP, Forslund S, Le Chatelier E, Falony G, Pons N, Prifti E, Quinquis B, Roume H, Vieira-Silva S, Hansen TH, Pedersen HK, Lewinter C, Sønderskov NB, MetaCardis Consortium , Køber L, Vestergaard H, Hansen T, Zucker JD, Galan P, Dumas ME, Raes J, Oppert JM, Letunic I, Nielsen J, Bork P, Ehrlich SD, Stumvoll M, Pedersen O, Aron-Wisnewsky J, Clément K, Bäckhed F
2020 Dec 21; 11(1): 6448. PubMed: 33349634.
PDF627.
Imidazole propionate is increased in diabetes and associated with dietary patterns and altered microbial ecology.
Molinaro A, Bel Lassen P, Henricsson M, Wu H, Adriouch S, Belda E, Chakaroun R, Nielsen T, Bergh PO, Rouault C, André S, Marquet F, Andreelli F, Salem JE, Assmann K, Bastard JP, Forslund S, Le Chatelier E, Falony G, Pons N, Prifti E, Quinquis B, Roume H, Vieira-Silva S, Hansen TH, Pedersen HK, Lewinter C, Sønderskov NB, MetaCardis Consortium , Køber L, Vestergaard H, Hansen T, Zucker JD, Galan P, Dumas ME, Raes J, Oppert JM, Letunic I, Nielsen J, Bork P, Ehrlich SD, Stumvoll M, Pedersen O, Aron-Wisnewsky J, Clément K, Bäckhed F
2020 Nov 18; 11(1): 5881. PubMed: 33208748.
Abstract + PDFMicrobiota-host-diet interactions contribute to the development of metabolic diseases. Imidazole propionate is a novel microbially produced metabolite from histidine, which impairs glucose metabolism. Here, we show that subjects with prediabetes and diabetes in the MetaCardis cohort from three European countries have elevated serum imidazole propionate levels. Furthermore, imidazole propionate levels were increased in subjects with low bacterial gene richness and Bacteroides 2 enterotype, which have previously been associated with obesity. The Bacteroides 2 enterotype was also associated with increased abundance of the genes involved in imidazole propionate biosynthesis from dietary histidine. Since patients and controls did not differ in their histidine dietary intake, the elevated levels of imidazole propionate in type 2 diabetes likely reflects altered microbial metabolism of histidine, rather than histidine intake per se. Thus the microbiota may contribute to type 2 diabetes by generating imidazole propionate that can modulate host inflammation and metabolism.
626.
Glycogen accumulation, central carbon metabolism, and aging of hematopoietic stem and progenitor cells.
Poisa-Beiro L, Thoma J, Landry J, Sauer S, Yamamoto A, Eckstein V, Romanov N, Raffel S, Hoffmann GF, Bork P, Benes V, Gavin AC, Tanaka M, Ho AD
Abstract + PDFInspired by recent proteomic data demonstrating the upregulation of carbon and glycogen metabolism in aging human hematopoietic stem and progenitor cells (HPCs, CD34+ cells), this report addresses whether this is caused by elevated glycolysis of the HPCs on a per cell basis, or by a subpopulation that has become more glycolytic. The average glycogen content in individual CD34+ cells from older subjects (> 50 years) was 3.5 times higher and more heterogeneous compared to younger subjects (< 35 years). Representative glycolytic enzyme activities in HPCs confirmed a significant increase in glycolysis in older subjects. The HPCs from older subjects can be fractionated into three distinct subsets with high, intermediate, and low glucose uptake (GU) capacity, while the subset with a high GU capacity could scarcely be detected in younger subjects. Thus, we conclude that upregulated glycolysis in aging HPCs is caused by the expansion of a more glycolytic HPC subset. Since single-cell RNA analysis has also demonstrated that this subpopulation is linked to myeloid differentiation and increased proliferation, isolation and mechanistic characterization of this subpopulation can be utilized to elucidate specific targets for therapeutic interventions to restore the lineage balance of aging HPCs.
625.
Severe COVID-19 Is Marked by a Dysregulated Myeloid Cell Compartment.
Schulte-Schrepping J, Reusch N, Paclik D, Baßler K, Schlickeiser S, Zhang B, Krämer B, Krammer T, Brumhard S, Bonaguro L, De Domenico E, Wendisch D, Grasshoff M, Kapellos TS, Beckstette M, Pecht T, Saglam A, Dietrich O, Mei HE, Schulz AR, Conrad C, Kunkel D, Vafadarnejad E, Xu CJ, Horne A, Herbert M, Drews A, Thibeault C, Pfeiffer M, Hippenstiel S, Hocke A, Müller-Redetzky H, Heim KM, Machleidt F, Uhrig A, Bosquillon de Jarcy L, Jürgens L, Stegemann M, Glösenkamp CR, Volk HD, Goffinet C, Landthaler M, Wyler E, Georg P, Schneider M, Dang-Heine C, Neuwinger N, Kappert K, Tauber R, Corman V, Raabe J, Kaiser KM, Vinh MT, Rieke G, Meisel C, Ulas T, Becker M, Geffers R, Witzenrath M, Drosten C, Suttorp N, von Kalle C, Kurth F, Händler K, Schultze JL, Aschenbrenner AC, Li Y, Nattermann J, Sawitzki B, Saliba AE, Sander LE, Deutsche COVID-19 OMICS Initiative (DeCOI) , Angelov A, Bals R, Bartholomäus A, Becker A, Bezdan D, Bonifacio E, Bork P, Clavel T, Colome-Tatche M, Diefenbach A, Dilthey A, Fischer N, Förstner K, Frick JS, Gagneur J, Goesmann A, Hain T, Hummel M, Janssen S, Kalinowski J, Kallies R, Kehr B, Keller A, Kim-Hellmuth S, Klein C, Kohlbacher O, Korbel J, Kurth I, Landthaler M, Li Y, Ludwig K, Makarewicz O, Marz M, McHardy A, Mertes C, Nöthen M, Nürnberg P, Ohler U, Ossowski S, Overmann J, Peter S, Pfeffer K, Poetsch AR, Pühler A, Rajewsky N, Ralser M, Rieß O, Ripke S, Nunes da Rocha U, Rosenstiel P, Saliba AE, Sander LE, Sawitzki B, Schiffer P, Schulte EC, Schultze JL, Sczyrba A, Stegle O, Stoye J, Theis F, Vehreschild J, Vogel J, von Kleist M, Walker A, Walter J, Wieczorek D, Ziebuhr J
Abstract + PDFCoronavirus disease 2019 (COVID-19) is a mild to moderate respiratory tract infection, however, a subset of patients progress to severe disease and respiratory failure. The mechanism of protective immunity in mild forms and the pathogenesis of severe COVID-19 associated with increased neutrophil counts and dysregulated immune responses remain unclear. In a dual-center, two-cohort study, we combined single-cell RNA-sequencing and single-cell proteomics of whole-blood and peripheral-blood mononuclear cells to determine changes in immune cell composition and activation in mild versus severe COVID-19 (242 samples from 109 individuals) over time. HLA-DRCD11c inflammatory monocytes with an interferon-stimulated gene signature were elevated in mild COVID-19. Severe COVID-19 was marked by occurrence of neutrophil precursors, as evidence of emergency myelopoiesis, dysfunctional mature neutrophils, and HLA-DR monocytes. Our study provides detailed insights into the systemic immune response to SARS-CoV-2 infection and reveals profound alterations in the myeloid cell compartment associated with severe COVID-19.
624.
Tara Oceans: towards global ocean ecosystems biology.
Sunagawa S, Acinas SG, Bork P, Bowler C
2020 Aug 12; 18(8): 428-445. PubMed: 32398798.
Abstract + PDFA planetary-scale understanding of the ocean ecosystem, particularly in light of climate change, is crucial. Here, we review the work of Tara Oceans, an international, multidisciplinary project to assess the complexity of ocean life across comprehensive taxonomic and spatial scales. Using a modified sailing boat, the team sampled plankton at 210 globally distributed sites at depths down to 1,000 m. We describe publicly available resources of molecular, morphological and environmental data, and discuss how an ecosystems biology approach has expanded our understanding of plankton diversity and ecology in the ocean as a planetary, interconnected ecosystem. These efforts illustrate how global-scale concepts and data can help to integrate biological complexity into models and serve as a baseline for assessing ecosystem changes and the future habitability of our planet in the Anthropocene epoch.
623.
Die Erforschung des menschlichen Mikrobioms
Trojahn U, Wirbel J, Bork P, Zeller G
In: Von der Datenanalyse zum Verstehen komplexer biologischer Systems01 pp.64-69. BID: 23.
Publisher: Bruns Druckwelt GmbH & Co. KG, Minden
PDF622.
Diversity within species: interpreting strains in microbiomes.
2020 Sep 4; 18(9): 491-506. PubMed: 32499497.
Abstract + PDFStudying within-species variation has traditionally been limited to culturable bacterial isolates and low-resolution microbial community fingerprinting. Metagenomic sequencing and technical advances have enabled culture-free, high-resolution strain and subspecies analyses at high throughput and in complex environments. This holds great scientific promise but has also led to an overwhelming number of methods and terms to describe infraspecific variation. This Review aims to clarify these advances by focusing on the diversity within bacterial and archaeal species in the context of microbiomics. We cover foundational microevolutionary concepts relevant to population genetics and summarize how within-species variation can be studied and stratified directly within microbial communities with a focus on metagenomics. Finally, we describe how common applications of within-species variation can be achieved using metagenomic data. We aim to guide the selection of appropriate terms and analytical approaches to facilitate researchers in benefiting from the increasing availability of large, high-resolution microbiome genetic sequencing data.
621.
Statin therapy is associated with lower prevalence of gut microbiota dysbiosis.
Vieira-Silva S, Falony G, Belda E, Nielsen T, Aron-Wisnewsky J, Chakaroun R, Forslund SK, Assmann K, Valles-Colomer M, Nguyen TTD, Proost S, Prifti E, Tremaroli V, Pons N, Le Chatelier E, Andreelli F, Bastard JP, Coelho LP, Galleron N, Hansen TH, Hulot JS, Lewinter C, Pedersen HK, Quinquis B, Rouault C, Roume H, Salem JE, Søndertoft NB, Touch S, MetaCardis Consortium: , Dumas E-M , Ehrlich SD, Galan P, Gøtze JP, Hansen T, Holst JJ, Køber L, Letunic I, Nielsen J, Oppert J-M , Stumvoll M, Vestergaard H, Zucker J-D , Bork P, Pedersen O, Bäckhed F, Clément K, Raes J
Abstract + PDFMicrobiome community typing analyses have recently identified the Bacteroides2 (Bact2) enterotype, an intestinal microbiota configuration that is associated with systemic inflammation and has a high prevalence in loose stools in humans. Bact2 is characterized by a high proportion of Bacteroides, a low proportion of Faecalibacterium and low microbial cell densities, and its prevalence varies from 13% in a general population cohort to as high as 78% in patients with inflammatory bowel disease. Reported changes in stool consistency and inflammation status during the progression towards obesity and metabolic comorbidities led us to propose that these developments might similarly correlate with an increased prevalence of the potentially dysbiotic Bact2 enterotype. Here, by exploring obesity-associated microbiota alterations in the quantitative faecal metagenomes of the cross-sectional MetaCardis Body Mass Index Spectrum cohort (n = 888), we identify statin therapy as a key covariate of microbiome diversification. By focusing on a subcohort of participants that are not medicated with statins, we find that the prevalence of Bact2 correlates with body mass index, increasing from 3.90% in lean or overweight participants to 17.73% in obese participants. Systemic inflammation levels in Bact2-enterotyped individuals are higher than predicted on the basis of their obesity status, indicative of Bact2 as a dysbiotic microbiome constellation. We also observe that obesity-associated microbiota dysbiosis is negatively associated with statin treatment, resulting in a lower Bact2 prevalence of 5.88% in statin-medicated obese participants. This finding is validated in both the accompanying MetaCardis cardiovascular disease dataset (n = 282) and the independent Flemish Gut Flora Project population cohort (n = 2,345). The potential benefits of statins in this context will require further evaluation in a prospective clinical trial to ascertain whether the effect is reproducible in a randomized population and before considering their application as microbiota-modulating therapeutics.
2019 26 publication(s).
620.
Consent insufficient for data release-Response.
Amann RI, Baichoo S, Blencowe BJ, Bork P, Borodovsky M, Brooksbank C, Chain PSG, Colwell RR, Daffonchio DG, Danchin A, de Lorenzo V, Dorrestein PC, Finn RD, Fraser CM, Gilbert JA, Hallam SJ, Hugenholtz P, Ioannidis JPA, Jansson JK, Kim JF, Klenk HP, Klotz MG, Knight R, Konstantinidis KT, Kyrpides NC, Mason CE, McHardy AC, Meyer F, Ouzounis CA, Patrinos AAN, Podar M, Pollard KS, Ravel J, Muñoz AR, Roberts RJ, Rosselló-Móra R, Sansone SA, Schloss PD, Schriml LM, Setubal JC, Sorek R, Stevens RL, Tiedje JM, Turjanski A, Tyson GW, Ussery DW, Weinstock GM, White O, Whitman WB, Xenarios I
PDF619.
Toward unrestricted use of public genomic data.
Amann RI, Baichoo S, Blencowe BJ, Bork P, Borodovsky M, Brooksbank C, Chain PSG, Colwell RR, Daffonchio DG, Danchin A, de Lorenzo V, Dorrestein PC, Finn RD, Fraser CM, Gilbert JA, Hallam SJ, Hugenholtz P, Ioannidis JPA, Jansson JK, Kim JF, Klenk HP, Klotz MG, Knight R, Konstantinidis KT, Kyrpides NC, Mason CE, McHardy AC, Meyer F, Ouzounis CA, Patrinos AAN, Podar M, Pollard KS, Ravel J, Muñoz AR, Roberts RJ, Rosselló-Móra R, Sansone SA, Schloss PD, Schriml LM, Setubal JC, Sorek R, Stevens RL, Tiedje JM, Turjanski A, Tyson GW, Ussery DW, Weinstock GM, White O, Whitman WB, Xenarios I
PDF618.
Cost-effectiveness of non-invasive screening for alcohol-related liver fibrosis.
Asphaug L, Thiele M, Krag A, Melberg HO, GALAXY consortium , Anastasiadou E, Arumugam M, Bork P, Hansen T, Israelsen H, Juul L, Karsdal M, Legido-Quickley C, Trebicka J
2019 Oct 8; [Epub ahead of print] PubMed: 31595545.
Abstract + PDFAlcohol-related liver disease is often undetected until irreversible late-stage decompensated disease manifests. Consequently, there is an unmet need for effective and economically reasonable pathways to screen for advanced alcohol-related fibrosis. We used real-world data from a large biopsy-controlled study of excessive drinkers recruited from primary and secondary care, to evaluate the cost-effectiveness of four primary care initiated strategies: 1) routine liver function tests with follow-up ultrasonography for test-positives, 2) the enhanced liver fibrosis (ELF) test, with hospital liver stiffness measurement (LSM) for positives, 3) three-tier strategy using Forns Index to control before strategy two, 4) direct referral of all to LSM. We used linked decision trees and Markov models to evaluate outcomes short-term (cost-per-accurate-diagnosis) and long-term (quality-adjusted life-years, QALYs). For low-prevalence populations, ELF with LSM follow-up was most cost-effective, both short-term (accuracy 96%, 196$ per patient), and long-term incremental cost-effectiveness ratio (ICER) $5,387-8,430/QALY, depending on whether diagnostic testing had lasting or temporary effects on abstinence rates. Adding Forns Index decreased costs to $72 per patient and accuracy to 95%. The strategy resulted in less QALY's due to more false negatives, but an ICER of $3,012, making this strategy suited for areas with restricted access to ELF and TE, or lower willingness-to-pay. For high-prevalence populations, direct referral to LSM was highly cost-effective (accuracy 93%, $297 per patient), with ICERs between $490 and $1,037/QALY CONCLUSION: Non-invasive screening for advanced, alcohol-related fibrosis is a cost-effective intervention when different referral pathways are used according to the prevalence of advanced fibrosis. Patients in the primary healthcare sector should be tested with the ELF test followed by LSM if test-positive, whereas direct referral to LSM is highly cost-effective in high-prevalence cohorts.
617.
Newly designed 16S rRNA metabarcoding primers amplify diverse and novel archaeal taxa from the environment.
Bahram M, Anslan S, Hildebrand F, Bork P, Tedersoo L
2019 Aug 30; 11(4): 487-494. PubMed: 30058291.
Abstract + PDFHigh-throughput studies of microbial communities suggest that Archaea are a widespread component of microbial diversity in various ecosystems. However, proper quantification of archaeal diversity and community ecology remains limited, as sequence coverage of Archaea is usually low due to the inability of available prokaryotic primers to efficiently amplify archaeal compared to bacterial rRNA genes. To improve identification and quantification of Archaea, we designed and validated the utility of several primer pairs to efficiently amplify archaeal 16S rRNA genes based on up-to-date reference genes. We demonstrate that several of these primer pairs amplify phylogenetically diverse Archaea with high sequencing coverage, outperforming commonly used primers. Based on comparing the resulting long 16S rRNA gene fragments with public databases from all habitats, we found several novel family- to phylum-level archaeal taxa from topsoil and surface water. Our results suggest that archaeal diversity has been largely overlooked due to the limitations of available primers, and that improved primer pairs enable to estimate archaeal diversity more accurately. This article is protected by copyright. All rights reserved.
616.
[The gut microbiome in Parkinson disease].
Bedarf JR, Hildebrand F, Goeser F, Bork P, Wüllner U
2019 Feb 31; 90(2): 160-166. PubMed: 30171304.
Abstract + PDFThe vast majority of Parkinson's disease (PD) cases are of sporadic origin and despite extensive research in recent years, the etiology still remains unclear. Several current case control studies are aiming to characterize a putative PD-specific composition of the gut microbiome, reflecting the potential relevance of microbiota in the pathogenesis of PD. Although methodologies and cohort sizes differed, the currently available studies showed reproducible or consistent results in terms of PD-specific alterations to the intestinal bacteria. By applying metagenomic sequencing procedures, it is even possible to distinguish PD cases from healthy individuals at a very early disease stage by means of individually modified microbiota. Among others, microbiota that are associated with an altered intestinal barrier or immune function, such as Akkermansia, Lactobacillus, Faecalibacterium and Prevotella were significantly over-represented or under-represented. There may even be a prodromal microbiome, as a comparable microbial shift is also found in patients with rapid eye movement (REM) sleep behavior disorder (RBD), a risk factor for the later development of synucleinopathies, such as PD.
615.
NG-meta-profiler: fast processing of metagenomes using NGLess, a domain-specific language.
2019 Jun 3; 7(1): 84. PubMed: 31159881.
Abstract + PDFShotgun metagenomes contain a sample of all the genomic material in an environment, allowing for the characterization of a microbial community. In order to understand these communities, bioinformatics methods are crucial. A common first step in processing metagenomes is to compute abundance estimates of different taxonomic or functional groups from the raw sequencing data. Given the breadth of the field, computational solutions need to be flexible and extensible, enabling the combination of different tools into a larger pipeline.
614.
Ice-Age Climate Adaptations Trap the Alpine Marmot in a State of Low Genetic Diversity.
Gossmann TI, Shanmugasundram A, Börno S, Duvaux L, Lemaire C, Kuhl H, Klages S, Roberts LD, Schade S, Gostner JM, Hildebrand F, Vowinckel J, Bichet C, Mülleder M, Calvani E, Zelezniak A, Griffin JL, Bork P, Allaine D, Cohas A, Welch JJ, Timmermann B, Ralser M
Abstract + PDFSome species responded successfully to prehistoric changes in climate [1, 2], while others failed to adapt and became extinct [3]. The factors that determine successful climate adaptation remain poorly understood. We constructed a reference genome and studied physiological adaptations in the Alpine marmot (Marmota marmota), a large ground-dwelling squirrel exquisitely adapted to the "ice-age" climate of the Pleistocene steppe [4, 5]. Since the disappearance of this habitat, the rodent persists in large numbers in the high-altitude Alpine meadow [6, 7]. Genome and metabolome showed evidence of adaptation consistent with cold climate, affecting white adipose tissue. Conversely, however, we found that the Alpine marmot has levels of genetic variation that are among the lowest for mammals, such that deleterious mutations are less effectively purged. Our data rule out typical explanations for low diversity, such as high levels of consanguineous mating, or a very recent bottleneck. Instead, ancient demographic reconstruction revealed that genetic diversity was lost during the climate shifts of the Pleistocene and has not recovered, despite the current high population size. We attribute this slow recovery to the marmot's adaptive life history. The case of the Alpine marmot reveals a complicated relationship between climatic changes, genetic diversity, and conservation status. It shows that species of extremely low genetic diversity can be very successful and persist over thousands of years, but also that climate-adapted life history can trap a species in a persistent state of low genetic diversity.
613.
Marine DNA Viral Macro- and Microdiversity from Pole to Pole.
Gregory AC, Zayed AA, Conceição-Neto N, Temperton B, Bolduc B, Alberti A, Ardyna M, Arkhipova K, Carmichael M, Cruaud C, Dimier C, Domínguez-Huerta G, Ferland J, Kandels S, Liu Y, Marec C, Pesant S, Picheral M, Pisarev S, Poulain J, Tremblay JÉ , Vik D, Tara Oceans coordinators , Babin M, Bowler C, Culley AI, De Vargas C, Dutilh BE, Iudicone D, Karp-Boss L, Roux S, Sunagawa S, Wincker P, Sullivan MB, Collaborators , Acinas SG, Babin M, Bork P, Boss E, Bowler C, Cochrane G, De Vargas C, Follows M, Gorsky G, Grimsley N, Guidi L, Hingamp P, Iudicone D, Jaillon O, Kandels-Lewis S, Karp-Boss L, Karsenti E, Not F, Ogata H, Pesant S, Poulton N, Raes J, Sardet C, Speich S, Stemmann L, Sullivan MB, Sunagawa S, Wincker P.
Abstract + PDFMicrobes drive most ecosystems and are modulated by viruses that impact their lifespan, gene flow, and metabolic outputs. However, ecosystem-level impacts of viral community diversity remain difficult to assess due to classification issues and few reference genomes. Here, we establish an ∼12-fold expanded global ocean DNA virome dataset of 195,728 viral populations, now including the Arctic Ocean, and validate that these populations form discrete genotypic clusters. Meta-community analyses revealed five ecological zones throughout the global ocean, including two distinct Arctic regions. Across the zones, local and global patterns and drivers in viral community diversity were established for both macrodiversity (inter-population diversity) and microdiversity (intra-population genetic variation). These patterns sometimes, but not always, paralleled those from macro-organisms and revealed temperate and tropical surface waters and the Arctic as biodiversity hotspots and mechanistic hypotheses to explain them. Such further understanding of ocean viruses is critical for broader inclusion in ecosystem models.
612.
Quantitative Proteome Landscape of the NCI-60 Cancer Cell Lines.
Guo T, Luna A, Rajapakse VN, Koh CC, Wu Z, Liu W, Sun Y, Gao H, Menden MP, Xu C, Calzone L, Martignetti L, Auwerx C, Buljan M, Banaei-Esfahani A, Ori A, Iskar M, Gillet L, Bi R, Zhang J, Zhang H, Yu C, Zhong Q, Varma S, Schmitt U, Qiu P, Zhang Q, Zhu Y, Wild PJ, Garnett MJ, Bork P, Beck M, Liu K, Saez-Rodriguez J, Elloumi F, Reinhold WC, Sander C, Pommier Y, Aebersold R
Abstract + PDFHere we describe a proteomic data resource for the NCI-60 cell lines generated by pressure cycling technology and SWATH mass spectrometry. We developed the DIA-expert software to curate and visualize the SWATH data, leading to reproducible detection of over 3,100 SwissProt proteotypic proteins and systematic quantification of pathway activities. Stoichiometric relationships of interacting proteins for DNA replication, repair, the chromatin remodeling NuRD complex, β-catenin, RNA metabolism, and prefoldins are more evident than that at the mRNA level. The data are available in CellMiner (discover.nci.nih.gov/cellminercdb and discover.nci.nih.gov/cellminer), allowing casual users to test hypotheses and perform integrative, cross-database analyses of multi-omic drug response correlations for over 20,000 drugs. We demonstrate the value of proteome data in predicting drug response for over 240 clinically relevant chemotherapeutic and targeted therapies. In summary, we present a novel proteome resource for the NCI-60, together with relevant software tools, and demonstrate the benefit of proteome analyses.
611.
Sample Preservation and Storage Significantly Impact Taxonomic and Functional Profiles in Metaproteomics Studies of the Human Gut Microbiome.
Hickl O, Heintz-Buschart A, Trautwein-Schult A, Hercog R, Bork P, Wilmes P, Becher D
2019 Sep 19; 7(9): . PubMed: 31546776.
Abstract + PDFWith the technological advances of the last decade, it is now feasible to analyze microbiome samples, such as human stool specimens, using multi-omic techniques. Given the inherent sample complexity, there exists a need for sample methods which preserve as much information as possible about the biological system at the time of sampling. Here, we analyzed human stool samples preserved and stored using different methods, applying metagenomics as well as metaproteomics. Our results demonstrate that sample preservation and storage have a significant effect on the taxonomic composition of identified proteins. The overall identification rates, as well as the proportion of proteins from were much higher when samples were flash frozen. Preservation in RNAlater overall led to fewer protein identifications and a considerable increase in the share of , as well as . Additionally, a decrease in the share of metabolism-related proteins and an increase of the relative amount of proteins involved in the processing of genetic information was observed for RNAlater-stored samples. This suggests that great care should be taken in choosing methods for the preservation and storage of microbiome samples, as well as in comparing the results of analyses using different sampling and storage methods. Flash freezing and subsequent storage at -80 °C should be chosen wherever possible.
610.
Antibiotics-induced monodominance of a novel gut bacterial order.
Hildebrand F, Moitinho-Silva L, Blasche S, Jahn MTT, Gossmann TI, Huerta-Cepas J, Hercog R, Luetge M, Bahram M, Pryszlak A, Alves RJ, Waszak SM, Zhu A, Ye L, Costea PI, Aalvink S, Belzer C, Forslund SK, Sunagawa S, Hentschel U, Merten C, Patil KR, Benes V, Bork P
Abstract + PDFThe composition of the healthy human adult gut microbiome is relatively stable over prolonged periods, and representatives of the most highly abundant and prevalent species have been cultured and described. However, microbial abundances can change on perturbations, such as antibiotics intake, enabling the identification and characterisation of otherwise low abundant species.
609.
eggNOG 5.0: a hierarchical, functionally and phylogenetically annotated orthology resource based on 5090 organisms and 2502 viruses.
Huerta-Cepas J, Szklarczyk D, Heller D, Hernández-Plaza A, Forslund SK, Cook H, Mende DR, Letunic I, Rattei T, Jensen LJ, von Mering C, Bork P
2019 Jan 8; 47: D309-D314. PubMed: 30418610.
Abstract + PDFeggNOG is a public database of orthology relationships, gene evolutionary histories and functional annotations. Here, we present version 5.0, featuring a major update of the underlying genome sets, which have been expanded to 4445 representative bacteria and 168 archaea derived from 25 038 genomes, as well as 477 eukaryotic organisms and 2502 viral proteomes that were selected for diversity and filtered by genome quality. In total, 4.4M orthologous groups (OGs) distributed across 379 taxonomic levels were computed together with their associated sequence alignments, phylogenies, HMM models and functional descriptors. Precomputed evolutionary analysis provides fine-grained resolution of duplication/speciation events within each OG. Our benchmarks show that, despite doubling the amount of genomes, the quality of orthology assignments and functional annotations (80% coverage) has persisted without significant changes across this update. Finally, we improved eggNOG online services for fast functional annotation and orthology prediction of custom genomics or metagenomics datasets. All precomputed data are publicly available for downloading or via API queries at http://eggnog.embl.de.
608.
Global Trends in Marine Plankton Diversity across Kingdoms of Life.
Ibarbalz FM, Henry N, Brandão MC, Martini S, Busseni G, Byrne H, Coelho LP, Endo H, Gasol JM, Gregory AC, Mahé F, Rigonato J, Royo-Llonch M, Salazar G, Sanz-Sáez I, Scalco E, Soviadan D, Zayed AA, Zingone A, Labadie K, Ferland J, Marec C, Kandels S, Picheral M, Dimier C, Poulain J, Pisarev S, Carmichael M, Pesant S, Tara Oceans coordinators , Babin M, Boss E, Iudicone D, Jaillon O, Acinas SG, Ogata H, Pelletier E, Stemmann L, Sullivan MB, Sunagawa S, Bopp L, De Vargas C, Karp-Boss L, Wincker P, Lombard F, Bowler C, Zinger L, Collaborators , Acinas SG, Babin M, Bork P, Boss E, Bowler C, Cochrane G, De Vargas C, Follows M, Gorsky G, Grimsley N, Guidi L, Hingamp P, Iudicone D, Jaillon O, Kandels S, Karp-Boss L, Karsenti E, Not F, Ogata H, Pesant S, Poulton N, Raes J, Sardet C, Speich S, Stemmann L, Sullivan MB, Sunagawa S, Wincker P.
Abstract + PDFThe ocean is home to myriad small planktonic organisms that underpin the functioning of marine ecosystems. However, their spatial patterns of diversity and the underlying drivers remain poorly known, precluding projections of their responses to global changes. Here we investigate the latitudinal gradients and global predictors of plankton diversity across archaea, bacteria, eukaryotes, and major virus clades using both molecular and imaging data from Tara Oceans. We show a decline of diversity for most planktonic groups toward the poles, mainly driven by decreasing ocean temperatures. Projections into the future suggest that severe warming of the surface ocean by the end of the 21 century could lead to tropicalization of the diversity of most planktonic groups in temperate and polar regions. These changes may have multiple consequences for marine ecosystem functioning and services and are expected to be particularly significant in key areas for carbon sequestration, fisheries, and marine conservation. VIDEO ABSTRACT.
607.
Interactive Tree Of Life (iTOL) v4: recent updates and new developments.
Letunic I, Bork P
2019 Jul 2; 47: W256-W259. PubMed: 30931475.
Abstract + PDFThe Interactive Tree Of Life (https://itol.embl.de) is an online tool for the display, manipulation and annotation of phylogenetic and other trees. It is freely available and open to everyone. The current version introduces four new dataset types, together with numerous new features. Annotation options have been expanded and new control options added for many display elements. An interactive spreadsheet-like editor has been implemented, providing dataset creation and editing directly in the web interface. Font support has been rewritten with full support for UTF-8 character encoding throughout the user interface. Google Web Fonts are now fully supported in the tree text labels. iTOL v4 is the first tool which supports direct visualization of Qiime 2 trees and associated annotations. The user account system has been streamlined and expanded with new navigation options, and currently handles >700 000 trees from more than 40 000 individual users. Full batch access has been implemented allowing programmatic upload and export of trees and annotations.
606.
Efficacy of probiotics to prevent gut dysbiosis in preterm infants of 28+0-32+6 weeks of gestation: a randomised, placebo-controlled, double-blind, multicentre trial: the PRIMAL Clinical Study protocol.
Marißen J, Haiß A, Meyer C, Van Rossum T, Bünte LM, Frommhold D, Gille C, Goedicke-Fritz S, Göpel W, Hudalla H, Pagel J, Pirr S, Siller B, Viemann D, Vens M, König I, Herting E, Zemlin M, Gehring S, Bork P, Henneke P, Härtel C, PRIMAL consortium
Abstract + PDFThe healthy 'eubiosis' microbiome in infancy is regarded as the microbiome derived from term, vaginally delivered, antibiotic free, breastfed infants at 4-6 months. Dysbiosis is regarded as a deviation from a healthy state with reduced microbial diversity and deficient capacity to control drug-resistant organisms. Preterm infants are highly sensitive to early gut dysbiosis. Latter has been associated with sepsis and necrotising enterocolitis, but may also contribute to long-term health problems. Probiotics hold promise to reduce the risk for adverse short-term outcomes but the evidence from clinical trials remains inconclusive and none has directly assessed the effects of probiotics on the microbiome at high resolution.
605.
Microbial abundance, activity and population genomic profiling with mOTUs2.
Milanese A, Mende DR, Paoli L, Salazar G, Ruscheweyh HJ, Cuenca M, Hingamp P, Alves RJ, Costea PI, Coelho LP, Schmidt TSB, Almeida A, Mitchell AL, Finn RD, Huerta-Cepas J, Bork P, Zeller G, Sunagawa S
2019 Mar 4; 10(1): 1014. PubMed: 30833550.
Abstract + PDFMetagenomic sequencing has greatly improved our ability to profile the composition of environmental and host-associated microbial communities. However, the dependency of most methods on reference genomes, which are currently unavailable for a substantial fraction of microbial species, introduces estimation biases. We present an updated and functionally extended tool based on universal (i.e., reference-independent), phylogenetic marker gene (MG)-based operational taxonomic units (mOTUs) enabling the profiling of >7700 microbial species. As more than 30% of them could not previously be quantified at this taxonomic resolution, relative abundance estimates based on mOTUs are more accurate compared to other methods. As a new feature, we show that mOTUs, which are based on essential housekeeping genes, are demonstrably well-suited for quantification of basal transcriptional activity of community members. Furthermore, single nucleotide variation profiles estimated using mOTUs reflect those from whole genomes, which allows for comparing microbial strain populations (e.g., across different human body sites).
604.
InterPro in 2019: improving coverage, classification and access to protein sequence annotations.
Mitchell AL, Attwood TK, Babbitt PC, Blum M, Bork P, Bridge A, Brown SD, Chang HY, El-Gebali S, Fraser MI, Gough J, Haft DR, Huang H, Letunic I, Lopez R, Luciani A, Madeira F, Marchler-Bauer A, Mi H, Natale DA, Necci M, Nuka G, Orengo C, Pandurangan AP, Paysan-Lafosse T, Pesseat S, Potter SC, Qureshi MA, Rawlings ND, Redaschi N, Richardson LJ, Rivoire C, Salazar GA, Sangrador-Vegas A, Sigrist CJA, Sillitoe I, Sutton GG, Thanki N, Thomas PD, Tosatto SCE, Yong SY, Finn RD
2019 Jan 8; 47: D351-D360. PubMed: 30398656.
Abstract + PDFThe InterPro database (http://www.ebi.ac.uk/interpro/) classifies protein sequences into families and predicts the presence of functionally important domains and sites. Here, we report recent developments with InterPro (version 70.0) and its associated software, including an 18% growth in the size of the database in terms on new InterPro entries, updates to content, the inclusion of an additional entry type, refined modelling of discontinuous domains, and the development of a new programmatic interface and website. These developments extend and enrich the information provided by InterPro, and provide greater flexibility in terms of data access. We also show that InterPro's sequence coverage has kept pace with the growth of UniProtKB, and discuss how our evaluation of residue coverage may help guide future curation activities.
603.
Disentangling Genetic and Environmental Effects on the Proteotypes of Individuals.
Abstract + PDFProteotypes, like genotypes, have been found to vary between individuals in several studies, but consistent molecular functional traits across studies remain to be quantified. In a meta-analysis of 11 proteomics datasets from humans and mice, we use co-variation of proteins in known functional modules across datasets and individuals to obtain a consensus landscape of proteotype variation. We find that individuals differ considerably in both protein complex abundances and stoichiometry. We disentangle genetic and environmental factors impacting these metrics, with genetic sex and specific diets together explaining 13.5% and 11.6% of the observed variation of complex abundance and stoichiometry, respectively. Sex-specific differences, for example, include various proteins and complexes, where the respective genes are not located on sex-specific chromosomes. Diet-specific differences, added to the individual genetic backgrounds, might become a starting point for personalized proteotype modulation toward desired features.
602.
Minimum Information about an Uncultivated Virus Genome (MIUViG).
Roux S, Adriaenssens EM, Dutilh BE, Koonin EV, Kropinski AM, Krupovic M, Kuhn JH, Lavigne R, Brister JR, Varsani A, Amid C, Aziz RK, Bordenstein SR, Bork P, Breitbart M, Cochrane GR, Daly RA, Desnues C, Duhaime MB, Emerson JB, Enault F, Fuhrman JA, Hingamp P, Hugenholtz P, Hurwitz BL, Ivanova NN, Labonté JM, Lee KB, Malmstrom RR, Martinez-Garcia M, Mizrachi IK, Ogata H, Páez-Espino D, Petit MA, Putonti C, Rattei T, Reyes A, Rodriguez-Valera F, Rosario K, Schriml L, Schulz F, Steward GF, Sullivan MB, Sunagawa S, Suttle CA, Temperton B, Tringe SG, Thurber RV, Webster NS, Whiteson KL, Wilhelm SW, Wommack KE, Woyke T, Wrighton KC, Yilmaz P, Yoshida T, Young MJ, Yutin N, Allen LZ, Kyrpides NC, Eloe-Fadrosh EA
2019 Jan 17; 37(1): 29-37. PubMed: 30556814.
Abstract + PDFWe present an extension of the Minimum Information about any (x) Sequence (MIxS) standard for reporting sequences of uncultivated virus genomes. Minimum Information about an Uncultivated Virus Genome (MIUViG) standards were developed within the Genomic Standards Consortium framework and include virus origin, genome quality, genome annotation, taxonomic classification, biogeographic distribution and in silico host prediction. Community-wide adoption of MIUViG standards, which complement the Minimum Information about a Single Amplified Genome (MISAG) and Metagenome-Assembled Genome (MIMAG) standards for uncultivated bacteria and archaea, will improve the reporting of uncultivated virus genomes in public databases. In turn, this should enable more robust comparative studies and a systematic exploration of the global virosphere.
601.
Gene Expression Changes and Community Turnover Differentially Shape the Global Ocean Metatranscriptome.
Salazar G, Paoli L, Alberti A, Huerta-Cepas J, Ruscheweyh HJ, Cuenca M, Field CM, Coelho LP, Cruaud C, Engelen S, Gregory AC, Labadie K, Marec C, Pelletier E, Royo-Llonch M, Roux S, Sánchez P, Uehara H, Zayed AA, Zeller G, Carmichael M, Dimier C, Ferland J, Kandels S, Picheral M, Pisarev S, Poulain J, Tara Oceans Consortium Coordinators , Acinas SG, Babin M, Bork P, Bowler C, De Vargas C, Guidi L, Hingamp P, Iudicone D, Karp-Boss L, Karsenti E, Ogata H, Pesant S, Speich S, Sullivan MB, Wincker P, Sunagawa S
Abstract + PDFOcean microbial communities strongly influence the biogeochemistry, food webs, and climate of our planet. Despite recent advances in understanding their taxonomic and genomic compositions, little is known about how their transcriptomes vary globally. Here, we present a dataset of 187 metatranscriptomes and 370 metagenomes from 126 globally distributed sampling stations and establish a resource of 47 million genes to study community-level transcriptomes across depth layers from pole-to-pole. We examine gene expression changes and community turnover as the underlying mechanisms shaping community transcriptomes along these axes of environmental variation and show how their individual contributions differ for multiple biogeochemically relevant processes. Furthermore, we find the relative contribution of gene expression changes to be significantly lower in polar than in non-polar waters and hypothesize that in polar regions, alterations in community activity in response to ocean warming will be driven more strongly by changes in organismal composition than by gene regulatory mechanisms. VIDEO ABSTRACT.
600.
Extensive transmission of microbes along the gastrointestinal tract.
Schmidt TSB, Hayward MR, Coelho LP, Li SS, Costea PI, Voigt AY, Wirbel J, Maistrenko OM, Alves RJ, Bergsten E, de Beaufort C, Sobhani I, Heintz-Buschart A, Sunagawa S, Zeller G, Wilmes P, Bork P
Abstract + PDFThe gastrointestinal tract is abundantly colonized by microbes, yet the translocation of oral species to the intestine is considered a rare aberrant event, and a hallmark of disease. By studying salivary and fecal microbial strain populations of 310 species in 470 individuals from five countries, we found that transmission to, and subsequent colonization of, the large intestine by oral microbes is common and extensive among healthy individuals. We found evidence for a vast majority of oral species to be transferable, with increased levels of transmission in colorectal cancer and rheumatoid arthritis patients and, more generally, for species described as opportunistic pathogens. This establishes the oral cavity as an endogenous reservoir for gut microbial strains, and oral-fecal transmission as an important process that shapes the gastrointestinal microbiome in health and disease.
599.
STRING v11: protein-protein association networks with increased coverage, supporting functional discovery in genome-wide experimental datasets.
Szklarczyk D, Gable AL, Lyon D, Junge A, Wyder S, Huerta-Cepas J, Simonovic M, Doncheva NT, Morris JH, Bork P, Jensen LJ, von Mering C
2019 Jan 8; 47: D607-D613. PubMed: 30476243.
Abstract + PDFProteins and their functional interactions form the backbone of the cellular machinery. Their connectivity network needs to be considered for the full understanding of biological phenomena, but the available information on protein-protein associations is incomplete and exhibits varying levels of annotation granularity and reliability. The STRING database aims to collect, score and integrate all publicly available sources of protein-protein interaction information, and to complement these with computational predictions. Its goal is to achieve a comprehensive and objective global network, including direct (physical) as well as indirect (functional) interactions. The latest version of STRING (11.0) more than doubles the number of organisms it covers, to 5090. The most important new feature is an option to upload entire, genome-wide datasets as input, allowing users to visualize subsets as interaction networks and to perform gene-set enrichment analysis on the entire input. For the enrichment analysis, STRING implements well-known classification systems such as Gene Ontology and KEGG, but also offers additional, new classification systems based on high-throughput text-mining as well as on a hierarchical clustering of the association network itself. The STRING resource is available online at https://string-db.org/.
598.
Metagenomic analysis of colorectal cancer datasets identifies cross-cohort microbial diagnostic signatures and a link with choline degradation.
Thomas AM, Manghi P, Asnicar F, Pasolli E, Armanini F, Zolfo M, Beghini F, Manara S, Karcher N, Pozzi C, Gandini S, Serrano D, Tarallo S, Francavilla A, Gallo G, Trompetto M, Ferrero G, Mizutani S, Shiroma H, Shiba S, Shibata T, Yachida S, Yamada T, Wirbel J, Schrotz-King P, Ulrich CM, Brenner H, Arumugam M, Bork P, Zeller G, Cordero F, Dias-Neto E, Setubal JC, Tett A, Pardini B, Rescigno M, Waldron L, Naccarati A, Segata N
Abstract + PDFSeveral studies have investigated links between the gut microbiome and colorectal cancer (CRC), but questions remain about the replicability of biomarkers across cohorts and populations. We performed a meta-analysis of five publicly available datasets and two new cohorts and validated the findings on two additional cohorts, considering in total 969 fecal metagenomes. Unlike microbiome shifts associated with gastrointestinal syndromes, the gut microbiome in CRC showed reproducibly higher richness than controls (P < 0.01), partially due to expansions of species typically derived from the oral cavity. Meta-analysis of the microbiome functional potential identified gluconeogenesis and the putrefaction and fermentation pathways as being associated with CRC, whereas the stachyose and starch degradation pathways were associated with controls. Predictive microbiome signatures for CRC trained on multiple datasets showed consistently high accuracy in datasets not considered for model training and independent validation cohorts (average area under the curve, 0.84). Pooled analysis of raw metagenomes showed that the choline trimethylamine-lyase gene was overabundant in CRC (P = 0.001), identifying a relationship between microbiome choline metabolism and CRC. The combined analysis of heterogeneous CRC cohorts thus identified reproducible microbiome biomarkers and accurate disease-predictive models that can form the basis for clinical prognostic tests and hypothesis-driven mechanistic studies.
597.
Author Correction: Metagenomic analysis of colorectal cancer datasets identifies cross-cohort microbial diagnostic signatures and a link with choline degradation.
Thomas AM, Manghi P, Asnicar F, Pasolli E, Armanini F, Zolfo M, Beghini F, Manara S, Karcher N, Pozzi C, Gandini S, Serrano D, Tarallo S, Francavilla A, Gallo G, Trompetto M, Ferrero G, Mizutani S, Shiroma H, Shiba S, Shibata T, Yachida S, Yamada T, Wirbel J, Schrotz-King P, Ulrich CM, Brenner H, Arumugam M, Bork P, Zeller G, Cordero F, Dias-Neto E, Setubal JC, Tett A, Pardini B, Rescigno M, Waldron L, Naccarati A, Segata N
Abstract + PDFAn amendment to this paper has been published and can be accessed via a link at the top of the paper.
596.
Population-level analysis of subtype prevalence and variation in the human gut microbiota.
Tito RY, Chaffron S, Caenepeel C, Lima-Mendez G, Wang J, Vieira-Silva S, Falony G, Hildebrand F, Darzi Y, Rymenans L, Verspecht C, Bork P, Vermeire S, Joossens M, Raes J
Abstract + PDFHuman gut microbiome studies are mainly bacteria- and archaea-oriented, overlooking the presence of single-cell eukaryotes such as an enteric stramenopiles with worldwide distribution. Here, we surveyed the prevalence and subtype variation of in faecal samples collected as part of the Flemish Gut Flora Project (FGFP), a Western population cohort. We assessed potential links between subtypes and identified microbiota-host covariates and quantified microbiota differentiation relative to subtype abundances.
595.
Meta-analysis of fecal metagenomes reveals global microbial signatures that are specific for colorectal cancer.
Wirbel J, Pyl PT, Kartal E, Zych K, Kashani A, Milanese A, Fleck JS, Voigt AY, Palleja A, Ponnudurai R, Sunagawa S, Coelho LP, Schrotz-King P, Vogtmann E, Habermann N, Niméus E, Thomas AM, Manghi P, Gandini S, Serrano D, Mizutani S, Shiroma H, Shiba S, Shibata T, Yachida S, Yamada T, Waldron L, Naccarati A, Segata N, Sinha R, Ulrich CM, Brenner H, Arumugam M, Bork P, Zeller G
Abstract + PDFAssociation studies have linked microbiome alterations with many human diseases. However, they have not always reported consistent results, thereby necessitating cross-study comparisons. Here, a meta-analysis of eight geographically and technically diverse fecal shotgun metagenomic studies of colorectal cancer (CRC, n = 768), which was controlled for several confounders, identified a core set of 29 species significantly enriched in CRC metagenomes (false discovery rate (FDR) < 1 × 10). CRC signatures derived from single studies maintained their accuracy in other studies. By training on multiple studies, we improved detection accuracy and disease specificity for CRC. Functional analysis of CRC metagenomes revealed enriched protein and mucin catabolism genes and depleted carbohydrate degradation genes. Moreover, we inferred elevated production of secondary bile acids from CRC metagenomes, suggesting a metabolic link between cancer-associated gut microbes and a fat- and meat-rich diet. Through extensive validations, this meta-analysis firmly establishes globally generalizable, predictive taxonomic and functional microbiome CRC signatures as a basis for future diagnostics.
2018 27 publication(s).
594.
Structure and function of the global topsoil microbiome.
Bahram M, Hildebrand F, Forslund SK, Anderson JL, Soudzilovskaia NA, Bodegom PM, Bengtsson-Palme J, Anslan S, Coelho LP, Harend H, Huerta-Cepas J, Medema MH, Maltz MR, Mundra S, Olsson PA, Pent M, Põlme S, Sunagawa S, Ryberg M, Tedersoo L, Bork P
Abstract + PDFSoils harbour some of the most diverse microbiomes on Earth and are essential for both nutrient cycling and carbon storage. To understand soil functioning, it is necessary to model the global distribution patterns and functional gene repertoires of soil microorganisms, as well as the biotic and environmental associations between the diversity and structure of both bacterial and fungal soil communities. Here we show, by leveraging metagenomics and metabarcoding of global topsoil samples (189 sites, 7,560 subsamples), that bacterial, but not fungal, genetic diversity is highest in temperate habitats and that microbial gene composition varies more strongly with environmental variables than with geographic distance. We demonstrate that fungi and bacteria show global niche differentiation that is associated with contrasting diversity responses to precipitation and soil pH. Furthermore, we provide evidence for strong bacterial-fungal antagonism, inferred from antibiotic-resistance genes, in topsoil and ocean habitats, indicating the substantial role of biotic interactions in shaping microbial communities. Our results suggest that both competition and environmental filtering affect the abundance, composition and encoded gene functions of bacterial and fungal communities, indicating that the relative contributions of these microorganisms to global nutrient cycling varies spatially.
593.
Pervasive Protein Thermal Stability Variation during the Cell Cycle.
Becher I, Andrés-Pons A, Romanov N, Stein F, Schramm M, Baudin F, Helm D, Kurzawa N, Mateus A, Mackmull MT, Typas A, Müller CW, Bork P, Beck M, Savitski MM
Abstract + PDFQuantitative mass spectrometry has established proteome-wide regulation of protein abundance and post-translational modifications in various biological processes. Here, we used quantitative mass spectrometry to systematically analyze the thermal stability and solubility of proteins on a proteome-wide scale during the eukaryotic cell cycle. We demonstrate pervasive variation of these biophysical parameters with most changes occurring in mitosis and G1. Various cellular pathways and components vary in thermal stability, such as cell-cycle factors, polymerases, and chromatin remodelers. We demonstrate that protein thermal stability serves as a proxy for enzyme activity, DNA binding, and complex formation in situ. Strikingly, a large cohort of intrinsically disordered and mitotically phosphorylated proteins is stabilized and solubilized in mitosis, suggesting a fundamental remodeling of the biophysical environment of the mitotic cell. Our data represent a rich resource for cell, structural, and systems biologists interested in proteome regulation during biological transitions.
592.
Corrigendum: Minimum information about a single amplified genome (MISAG) and a metagenome-assembled genome (MIMAG) of bacteria and archaea.
Bowers RM, Kyrpides NC, Stepanauskas R, Harmon-Smith M, Doud D, Reddy TBK, Schulz F, Jarett J, Rivers AR, Eloe-Fadrosh EA, Tringe SG, Ivanova NN, Copeland A, Clum A, Becraft ED, Malmstrom RR, Birren B, Podar M, Bork P, Weinstock GM, Garrity GM, Dodsworth JA, Yooseph S, Sutton G, Glöckner FO, Gilbert JA, Nelson WC, Hallam SJ, Jungbluth SP, Ettema TJG, Tighe S, Konstantinidis KT, Liu WT, Baker BJ, Rattei T, Eisen JA, Hedlund B, McMahon KD, Fierer N, Knight R, Finn R, Cochrane G, Karsch-Mizrachi I, Tyson GW, Rinke C
2018 Feb 6; 36(2): 196. PubMed: 29406516.
PDF591.
Corrigendum: Minimum information about a single amplified genome (MISAG) and a metagenome-assembled genome (MIMAG) of bacteria and archaea.
Bowers RM, Kyrpides NC, Stepanauskas R, Harmon-Smith M, Doud D, Reddy TBK, Schulz F, Jarett J, Rivers AR, Eloe-Fadrosh EA, Tringe SG, Ivanova NN, Copeland A, Clum A, Becraft ED, Malmstrom RR, Birren B, Podar M, Bork P, Weinstock GM, Garrity GM, Dodsworth JA, Yooseph S, Sutton G, Glöckner FO, Gilbert JA, Nelson WC, Hallam SJ, Jungbluth SP, Ettema TJG, Tighe S, Konstantinidis KT, Liu WT, Baker BJ, Rattei T, Eisen JA, Hedlund B, McMahon KD, Fierer N, Knight R, Finn R, Cochrane G, Karsch-Mizrachi I, Tyson GW, Rinke C
2018 Jul 6; 36(7): 660. PubMed: 29979671.
PDF590.
Species-specific activity of antibacterial drug combinations.
Brochado AR, Telzerow A, Bobonis J, Banzhaf M, Mateus A, Selkrig J, Huth E, Bassler S, Zamarreño Beas J, Zietek M, Ng N, Foerster S, Ezraty B, Py B, Barras F, Savitski MM, Bork P, Göttig S, Typas A
Abstract + PDFThe spread of antimicrobial resistance has become a serious public health concern, making once-treatable diseases deadly again and undermining the achievements of modern medicine. Drug combinations can help to fight multi-drug-resistant bacterial infections, yet they are largely unexplored and rarely used in clinics. Here we profile almost 3,000 dose-resolved combinations of antibiotics, human-targeted drugs and food additives in six strains from three Gram-negative pathogens-Escherichia coli, Salmonella enterica serovar Typhimurium and Pseudomonas aeruginosa-to identify general principles for antibacterial drug combinations and understand their potential. Despite the phylogenetic relatedness of the three species, more than 70% of the drug-drug interactions that we detected are species-specific and 20% display strain specificity, revealing a large potential for narrow-spectrum therapies. Overall, antagonisms are more common than synergies and occur almost exclusively between drugs that target different cellular processes, whereas synergies are more conserved and are enriched in drugs that target the same process. We provide mechanistic insights into this dichotomy and further dissect the interactions of the food additive vanillin. Finally, we demonstrate that several synergies are effective against multi-drug-resistant clinical isolates in vitro and during infections of the larvae of the greater wax moth Galleria mellonella, with one reverting resistance to the last-resort antibiotic colistin.
589.
A global ocean atlas of eukaryotic genes.
Carradec Q, Pelletier E, Da Silva C, Alberti A, Seeleuthner Y, Blanc-Mathieu R, Lima-Mendez G, Rocha F, Tirichine L, Labadie K, Kirilovsky A, Bertrand A, Engelen S, Madoui MA, Méheust R, Poulain J, Romac S, Richter DJ, Yoshikawa G, Dimier C, Kandels-Lewis S, Picheral M, Searson S, Tara-Oceans-Coordinators : , Jaillon O, Aury JM, Karsenti E, Sullivan MB, Sunagawa S, Bork P, Not F, Hingamp P, Raes J, Guidi L, Ogata H, De Vargas C, Iudicone D, Bowler C, Wincker P
2018 Jan 25; 9(1): 373. PubMed: 29371626.
Abstract + PDFWhile our knowledge about the roles of microbes and viruses in the ocean has increased tremendously due to recent advances in genomics and metagenomics, research on marine microbial eukaryotes and zooplankton has benefited much less from these new technologies because of their larger genomes, their enormous diversity, and largely unexplored physiologies. Here, we use a metatranscriptomics approach to capture expressed genes in open ocean Tara Oceans stations across four organismal size fractions. The individual sequence reads cluster into 116 million unigenes representing the largest reference collection of eukaryotic transcripts from any single biome. The catalog is used to unveil functions expressed by eukaryotic marine plankton, and to assess their functional biogeography. Almost half of the sequences have no similarity with known proteins, and a great number belong to new gene families with a restricted distribution in the ocean. Overall, the resource provides the foundations for exploring the roles of marine eukaryotes in ocean ecology and biogeochemistry.
588.
Similarity of the dog and human gut microbiomes in gene content and response to diet.
Coelho LP, Kultima JR, Costea PI, Fournier C, Pan Y, Czarnecki-Maulden G, Hayward MR, Forslund SK, Schmidt TSB, Descombes P, Jackson JR, Li Q, Bork P
2018 Apr 19; 6(1): 72. PubMed: 29669589.
Abstract + PDFGut microbes influence their hosts in many ways, in particular by modulating the impact of diet. These effects have been studied most extensively in humans and mice. In this work, we used whole genome metagenomics to investigate the relationship between the gut metagenomes of dogs, humans, mice, and pigs.
587.
Enterotypes in the landscape of gut microbial community composition.
Costea PI, Hildebrand F, Arumugam M, Bäckhed F, Blaser MJ, Bushman FD, de Vos WM, Ehrlich SD, Fraser CM, Hattori M, Huttenhower C, Jeffery IB, Knights D, Lewis JD, Ley RE, Ochman H, O'Toole PW, Quince C, Relman DA, Shanahan F, Sunagawa S, Wang J, Weinstock GM, Wu GD, Zeller G, Zhao L, Raes J, Knight R, Bork P
2018 Jan; 3(1): 8-16. PubMed: 29255284.
Abstract + PDFPopulation stratification is a useful approach for a better understanding of complex biological problems in human health and wellbeing. The proposal that such stratification applies to the human gut microbiome, in the form of distinct community composition types termed enterotypes, has been met with both excitement and controversy. In view of accumulated data and re-analyses since the original work, we revisit the concept of enterotypes, discuss different methods of dividing up the landscape of possible microbiome configurations, and put these concepts into functional, ecological and medical contexts. As enterotypes are of use in describing the gut microbial community landscape and may become relevant in clinical practice, we aim to reconcile differing views and encourage a balanced application of the concept.
586.
Publisher Correction: Enterotypes in the landscape of gut microbial community composition.
Costea PI, Hildebrand F, Arumugam M, Bäckhed F, Blaser MJ, Bushman FD, de Vos WM, Ehrlich SD, Fraser CM, Hattori M, Huttenhower C, Jeffery IB, Knights D, Lewis JD, Ley RE, Ochman H, O'Toole PW, Quince C, Relman DA, Shanahan F, Sunagawa S, Wang J, Weinstock GM, Wu GD, Zeller G, Zhao L, Raes J, Knight R, Bork P
2018 Mar 13; 3(3): 388. PubMed: 29440750.
Abstract + PDFIn the version of this Perspective originally published, the first and last name of co-author Manimozhiyan Arumugam were switched. This has now been corrected in all versions of the Perspective.
585.
iPath3.0: interactive pathways explorer v3.
2018 Jul 2; 46: W510-W513. PubMed: 29718427.
Abstract + PDFiPath3.0 (http://pathways.embl.de) is a web-application for the visualization and analysis of cellular pathways. It is freely available and open to everyone. Currently it is based on four KEGG global maps, which summarize up to 158 traditional KEGG pathway maps, 192 KEGG modules and other metabolic elements into one connected and manually curated metabolic network. Users can fully customize these networks and interactively explore them through its redesigned, fast and lightweight interface, which highlights general metabolic trends in multi-omics data. It also offers navigation at various levels of details to help users further investigate those trends and ultimately uncover novel biological insights. Support for multiple experimental conditions and time-series datasets, tools for generation of customization data, programmatic access, and a free user accounts system were introduced in this version to further streamline its workflow.
584.
Mother-to-Infant Microbial Transmission from Different Body Sites Shapes the Developing Infant Gut Microbiome.
Ferretti P, Pasolli E, Tett A, Asnicar F, Gorfer V, Fedi S, Armanini F, Truong DT, Manara S, Zolfo M, Beghini F, Bertorelli R, De Sanctis V, Bariletti I, Canto R, Clementi R, Cologna M, Crifò T, Cusumano G, Gottardi S, Innamorati C, Masè C, Postai D, Savoi D, Duranti S, Lugli GA, Mancabelli L, Turroni F, Ferrario C, Milani C, Mangifesta M, Anzalone R, Viappiani A, Yassour M, Vlamakis H, Xavier R, Collado CM, Koren O, Tateo S, Soffiati M, Pedrotti A, Ventura M, Huttenhower C, Bork P, Segata N
2018 Jul 11; 24(1): 133-145.e5. PubMed: 30001516.
Abstract + PDFThe acquisition and development of the infant microbiome are key to establishing a healthy host-microbiome symbiosis. The maternal microbial reservoir is thought to play a crucial role in this process. However, the source and transmission routes of the infant pioneering microbes are poorly understood. To address this, we longitudinally sampled the microbiome of 25 mother-infant pairs across multiple body sites from birth up to 4 months postpartum. Strain-level metagenomic profiling showed a rapid influx of microbes at birth followed by strong selection during the first few days of life. Maternal skin and vaginal strains colonize only transiently, and the infant continues to acquire microbes from distinct maternal sources after birth. Maternal gut strains proved more persistent in the infant gut and ecologically better adapted than those acquired from other sources. Together, these data describe the mother-to-infant microbiome transmission routes that are integral in the development of the infant microbiome.
583.
MVP: a microbe-phage interaction database.
2018 Jan 4; 46: D700-D707. PubMed: 29177508.
Abstract + PDFPhages invade microbes, accomplish host lysis and are of vital importance in shaping the community structure of environmental microbiota. More importantly, most phages have very specific hosts; they are thus ideal tools to manipulate environmental microbiota at species-resolution. The main purpose of MVP (Microbe Versus Phage) is to provide a comprehensive catalog of phage-microbe interactions and assist users to select phage(s) that can target (and potentially to manipulate) specific microbes of interest. We first collected 50 782 viral sequences from various sources and clustered them into 33 097 unique viral clusters based on sequence similarity. We then identified 26 572 interactions between 18 608 viral clusters and 9245 prokaryotes (i.e. bacteria and archaea); we established these interactions based on 30 321 evidence entries that we collected from published datasets, public databases and re-analysis of genomic and metagenomic sequences. Based on these interactions, we calculated the host range for each of the phage clusters and accordingly grouped them into subgroups such as 'species-', 'genus-' and 'family-' specific phage clusters. MVP is equipped with a modern, responsive and intuitive interface, and is freely available at: http://mvp.medgenius.info.
582.
Cell-specific proteome analyses of human bone marrow reveal molecular features of age-dependent functional decline.
Hennrich ML, Romanov N, Horn P, Jaeger S, Eckstein V, Steeples V, Ye F, Ding X, Poisa-Beiro L, Lai MC, Lang B, Boultwood J, Luft T, Zaugg JB, Pellagatti A, Bork P, Aloy P, Gavin AC, Ho AD
2018 Oct 1; 9(1): 4004. PubMed: 30275468.
Abstract + PDFDiminishing potential to replace damaged tissues is a hallmark for ageing of somatic stem cells, but the mechanisms remain elusive. Here, we present proteome-wide atlases of age-associated alterations in human haematopoietic stem and progenitor cells (HPCs) and five other cell populations that constitute the bone marrow niche. For each, the abundance of a large fraction of the ~12,000 proteins identified is assessed in 59 human subjects from different ages. As the HPCs become older, pathways in central carbon metabolism exhibit features reminiscent of the Warburg effect, where glycolytic intermediates are rerouted towards anabolism. Simultaneously, altered abundance of early regulators of HPC differentiation reveals a reduced functionality and a bias towards myeloid differentiation. Ageing causes alterations in the bone marrow niche too, and diminishes the functionality of the pathways involved in HPC homing. The data represent a valuable resource for further analyses, and for validation of knowledge gained from animal models.
581.
Gut microbiota composition is associated with environmental landscape in honey bees.
Jones JC, Fruciano C, Hildebrand F, Al Toufalilia H, Balfour NJ, Bork P, Engel P, Ratnieks FL, Hughes WO
Abstract + PDFThere is growing recognition that the gut microbial community regulates a wide variety of important functions in its animal hosts, including host health. However, the complex interactions between gut microbes and environment are still unclear. Honey bees are ecologically and economically important pollinators that host a core gut microbial community that is thought to be constant across populations. Here, we examined whether the composition of the gut microbial community of honey bees is affected by the environmental landscape the bees are exposed to. We placed honey bee colonies reared under identical conditions in two main landscape types for 6 weeks: either oilseed rape farmland or agricultural farmland distant to fields of flowering oilseed rape. The gut bacterial communities of adult bees from the colonies were then characterized and compared based on amplicon sequencing of the 16S rRNA gene. While previous studies have delineated a characteristic core set of bacteria inhabiting the honey bee gut, our results suggest that the broad environment that bees are exposed to has some influence on the relative abundance of some members of that microbial community. This includes known dominant taxa thought to have functions in nutrition and health. Our results provide evidence for an influence of landscape exposure on honey bee microbial community and highlight the potential effect of exposure to different environmental parameters, such as forage type and neonicotinoid pesticides, on key honey bee gut bacteria. This work emphasizes the complexity of the relationship between the host, its gut bacteria, and the environment and identifies target microbial taxa for functional analyses.
580.
The gut microbiome is associated with behavioural task in honey bees.
2018; 65(3): 419-429. PubMed: 30100619.
Abstract + PDFThe gut microbiome is recognised as playing an integral role in the health and ecology of a wide variety of animal taxa. However, the relationship between social behavioural traits and the microbial community has received little attention. Honey bees are highly social and the workers perform different behavioural tasks in the colony that cause them to be exposed to different local environments. Here we examined whether the gut microbial community composition of worker honey bees is associated with the behavioural tasks they perform, and therefore also the local environment they are exposed to. We set up five observation hives, in which all workers were matched in age and observed the behaviour of marked bees in each colony over 4 days. The gut bacterial communities of bees seen performing predominantly foraging or predominantly in nest tasks were then characterised and compared based on amplicon sequencing of the 16S rRNA gene. Our results show that some core members of the unique honey bee gut bacterial community are represented in different relative abundances in bees performing different behavioural tasks. The differentially represented bacterial taxa include some thought to be important in carbohydrate metabolism and transport, and also linked to bee health. The results suggest an influence of task-related local environment exposure and diet on the honey bee gut microbial community and identify focal core taxa for further functional analyses.
579.
Copy number variation analysis and targeted NGS in 77 families with suspected Lynch syndrome reveals novel potential causative genes.
Kayser K, Degenhardt F, Holzapfel S, Horpaopan S, Peters S, Spier I, Morak M, Vangala D, Rahner N, von Knebel-Doeberitz M, Schackert HK, Engel C, Büttner R, Wijnen J, Doerks T, Bork P, Moebus S, Herms S, Fischer S, Hoffmann P, Aretz S, Steinke-Lange V
2018 Dec 1; 143(11): 2800-2813. PubMed: 29987844.
Abstract + PDFIn many families with suspected Lynch syndrome (LS), no germline mutation in the causative mismatch repair (MMR) genes is detected during routine diagnostics. To identify novel causative genes for LS, the present study investigated 77 unrelated, mutation-negative patients with clinically suspected LS and a loss of MSH2 in tumor tissue. An analysis for genomic copy number variants (CNV) was performed, with subsequent next generation sequencing (NGS) of selected candidate genes in a subgroup of the cohort. Genomic DNA was genotyped using Illumina's HumanOmniExpress Bead Array. After quality control and filtering, 25 deletions and 16 duplications encompassing 73 genes were identified in 28 patients. No recurrent CNV was detected, and none of the CNVs affected the regulatory regions of MSH2. A total of 49 candidate genes from genomic regions implicated by the present CNV analysis and 30 known or assumed risk genes for colorectal cancer (CRC) were then sequenced in a subset of 38 patients using a customized NGS gene panel and Sanger sequencing. Single nucleotide variants were identified in 14 candidate genes from the CNV analysis. The most promising of these candidate genes were: (i) PRKCA, PRKDC, and MCM4, since a functional relation to MSH2 is predicted by network analysis; and (ii) CSMD1, as this is commonly mutated in CRC. Furthermore, six patients harbored POLE variants outside the exonuclease domain, suggesting that these might be implicated in hereditary CRC. Analyses in larger cohorts of suspected LS patients recruited via international collaborations are warranted to verify the present findings. This article is protected by copyright. All rights reserved.
578.
Selective maternal seeding and environment shape the human gut microbiome.
2018 Apr 1; 28(4): 561-568. PubMed: 29496731.
Abstract + PDFVertical transmission of bacteria from mother to infant at birth is postulated to initiate a life-long host-microbe symbiosis, playing an important role in early infant development. However, only the tracking of strictly defined unique microbial strains can clarify where the intestinal bacteria come from, how long the initial colonisers persist and whether colonisation by other strains from the environment can replace existing ones. Using rare single nucleotide variants in fecal metagenomes of infants and their family members, we show strong evidence of selective and persistent transmission of maternal strain populations to the vaginally born infant, and their occasional replacement by strains from the environment, including those from family members, in later childhood. Only strains from the classes Actinobacteria and Bacteroidia, which are essential components of the infant microbiome, are transmitted from the mother and persist for at least one year. In contrast, maternal strains of Clostridia, a dominant class in the mother's gut microbiome, are not observed in the infant. Caesarean-born infants show a striking lack of maternal transmission at birth. After the first year, strain influx from the family environment occurs, and continues even in adulthood. Fathers appear to be more frequently donors of novel strains to other family members than receivers. Thus, the infant gut is seeded by selected maternal bacteria, which expand to form a stable community, with a rare but stable continuing strain influx over time.
577.
Metagenomic analysis of gut microbial communities from a Central Asian population.
Kushugulova A, Forslund SK, Costea PI, Kozhakhmetov S, Khassenbekova Z, Urazova M, Nurgozhin T, Zhumadilov Z, Benberin V, Driessen M, Hercog R, Voigt AY, Benes V, Kandels-Lewis S, Sunagawa S, Letunic I, Bork P
Abstract + PDFChanges in the gut microbiota are increasingly recognised to be involved in many diseases. This ecosystem is known to be shaped by many factors, including climate, geography, host nutrition, lifestyle and medication. Thus, knowledge of varying populations with different habits is important for a better understanding of the microbiome.
576.
20 years of the SMART protein domain annotation resource.
Letunic I, Bork P
2018 Jan 4; 46: D493-D496. PubMed: 29040681.
Abstract + PDFSMART (Simple Modular Architecture Research Tool) is a web resource (http://smart.embl.de) for the identification and annotation of protein domains and the analysis of protein domain architectures. SMART version 8 contains manually curated models for more than 1300 protein domains, with approximately 100 new models added since our last update article (1). The underlying protein databases were synchronized with UniProt (2), Ensembl (3) and STRING (4), doubling the total number of annotated domains and other protein features to more than 200 million. In its 20th year, the SMART analysis results pages have been streamlined again and its information sources have been updated. SMART's vector based display engine has been extended to all protein schematics in SMART and rewritten to use the latest web technologies. The internal full text search engine has been redesigned and updated, resulting in greatly increased search speed.
575.
Extensive impact of non-antibiotic drugs on human gut bacteria.
Maier L, Pruteanu M, Kuhn M, Zeller G, Telzerow A, Anderson EE, Brochado AR, Fernandez KC, Dose H, Mori H, Patil KR, Bork P, Typas A
Abstract + PDFA few commonly used non-antibiotic drugs have recently been associated with changes in gut microbiome composition, but the extent of this phenomenon is unknown. Here, we screened more than 1,000 marketed drugs against 40 representative gut bacterial strains, and found that 24% of the drugs with human targets, including members of all therapeutic classes, inhibited the growth of at least one strain in vitro. Particular classes, such as the chemically diverse antipsychotics, were overrepresented in this group. The effects of human-targeted drugs on gut bacteria are reflected on their antibiotic-like side effects in humans and are concordant with existing human cohort studies. Susceptibility to antibiotics and human-targeted drugs correlates across bacterial species, suggesting common resistance mechanisms, which we verified for some drugs. The potential risk of non-antibiotics promoting antibiotic resistance warrants further exploration. Our results provide a resource for future research on drug-microbiome interactions, opening new paths for side effect control and drug repurposing, and broadening our view of antibiotic resistance.
574.
Recovery of gut microbiota of healthy adults following antibiotic exposure.
Palleja A, Mikkelsen KH, Forslund SK, Kashani A, Allin KH, Nielsen T, Hansen TH, Liang S, Feng Q, Zhang C, Pyl PT, Coelho LP, Yang H, Wang J, Typas A, Nielsen MF, Nielsen HB, Bork P, Wang J, Vilsbøll T, Hansen T, Knop FK, Arumugam M, Pedersen O
2018 Nov 22; 3(11): 1255-1265. PubMed: 30349083.
Abstract + PDFTo minimize the impact of antibiotics, gut microorganisms harbour and exchange antibiotics resistance genes, collectively called their resistome. Using shotgun sequencing-based metagenomics, we analysed the partial eradication and subsequent regrowth of the gut microbiota in 12 healthy men over a 6-month period following a 4-day intervention with a cocktail of 3 last-resort antibiotics: meropenem, gentamicin and vancomycin. Initial changes included blooms of enterobacteria and other pathobionts, such as Enterococcus faecalis and Fusobacterium nucleatum, and the depletion of Bifidobacterium species and butyrate producers. The gut microbiota of the subjects recovered to near-baseline composition within 1.5 months, although 9 common species, which were present in all subjects before the treatment, remained undetectable in most of the subjects after 180 days. Species that harbour β-lactam resistance genes were positively selected for during and after the intervention. Harbouring glycopeptide or aminoglycoside resistance genes increased the odds of de novo colonization, however, the former also decreased the odds of survival. Compositional changes under antibiotic intervention in vivo matched results from in vitro susceptibility tests. Despite a mild yet long-lasting imprint following antibiotics exposure, the gut microbiota of healthy young adults are resilient to a short-term broad-spectrum antibiotics intervention and their antibiotics resistance gene carriage modulates their recovery processes.
573.
Quantifying compartment-associated variations of protein abundance in proteomics data.
Parca L, Beck M, Bork P, Ori A
2018 Jul 2; 14(7): e8131. PubMed: 29967062.
Abstract + PDFQuantitative mass spectrometry enables to monitor the abundance of thousands of proteins across biological conditions. Currently, most data analysis approaches rely on the assumption that the majority of the observed proteins remain unchanged across compared samples. Thus, gross morphological differences between cell states, deriving from, e.g., differences in size or number of organelles, are often not taken into account. Here, we analyzed multiple published datasets and frequently observed that proteins associated with a particular cellular compartment collectively increase or decrease in their abundance between conditions tested. We show that such effects, arising from underlying morphological differences, can skew the outcome of differential expression analysis. We propose a method to detect and normalize morphological effects underlying proteomics data. We demonstrate the applicability of our method to different datasets and biological questions including the analysis of sub-cellular proteomes in the context of aging. Our method provides a complementary perspective to classical differential expression analysis and enables to uncouple overall abundance changes from stoichiometric variations within defined group of proteins.
572.
A computational framework to integrate high-throughput '-omics' datasets for the identification of potential mechanistic links.
Pedersen HK, Forslund SK, Gudmundsdottir V, Petersen AØ, Hildebrand F, Hyötyläinen T, Nielsen T, Hansen T, Bork P, Ehrlich SD, Brunak S, Oresic M, Pedersen O, Nielsen HB
2018 Dec 31; 13(12): 2781-2800. PubMed: 30382244.
Abstract + PDFWe recently presented a three-pronged association study that integrated human intestinal microbiome data derived from shotgun-based sequencing with untargeted serum metabolome data and measures of host physiology. Metabolome and microbiome data are high dimensional, posing a major challenge for data integration. Here, we present a step-by-step computational protocol that details and discusses the dimensionality-reduction techniques used and methods for subsequent integration and interpretation of such heterogeneous types of data. Dimensionality reduction was achieved through a combination of data normalization approaches, binning of co-abundant genes and metabolites, and integration of prior biological knowledge. The use of prior knowledge to overcome functional redundancy across microbiome species is one central advance of our method over available alternative approaches. Applying this framework, other investigators can integrate various '-omics' readouts with variables of host physiology or any other phenotype of interest (e.g., connecting host and microbiome readouts to disease severity or treatment outcome in a clinical cohort) in a three-pronged association analysis to identify potential mechanistic links to be tested in experimental settings. Although we originally developed the framework for a human metabolome-microbiome study, it is generalizable to other organisms and environmental metagenomes, as well as to studies including other -omics domains such as transcriptomics and proteomics. The provided R code runs in ~1 h on a standard PC.
571.
Transposase-DNA Complex Structures Reveal Mechanisms for Conjugative Transposition of Antibiotic Resistance.
Rubio-Cosials A, Schulz EC, Lambertsen L, Smyshlyaev G, Rojas-Cordova C, Forslund K, Karaca E, Bebel A, Bork P, Barabas O
Abstract + PDFConjugative transposition drives the emergence of multidrug resistance in diverse bacterial pathogens, yet the mechanisms are poorly characterized. The Tn1549 conjugative transposon propagates resistance to the antibiotic vancomycin used for severe drug-resistant infections. Here, we present four high-resolution structures of the conserved Y-transposase of Tn1549 complexed with circular transposon DNA intermediates. The structures reveal individual transposition steps and explain how specific DNA distortion and cleavage mechanisms enable DNA strand exchange with an absolute minimum homology requirement. This appears to uniquely allow Tn916-like conjugative transposons to bypass DNA homology and insert into diverse genomic sites, expanding gene transfer. We further uncover a structural regulatory mechanism that prevents premature cleavage of the transposon DNA before a suitable target DNA is found and generate a peptide antagonist that interferes with the transposase-DNA structure to block transposition. Our results reveal mechanistic principles of conjugative transposition that could help control the spread of antibiotic resistance genes.
570.
The Human Gut Microbiome: From Association to Modulation.
Abstract + PDFOur understanding of the human gut microbiome continues to evolve at a rapid pace, but practical application of thisknowledge is still in its infancy. This review discusses the type of studies that will be essential for translating microbiome research into targeted modulations with dedicated benefits for the human host.
569.
Single-cell genomics of multiple uncultured stramenopiles reveals underestimated functional diversity across oceans.
Seeleuthner Y, Mondy S, Lombard V, Carradec Q, Pelletier E, Wessner M, Leconte J, Mangot JF, Poulain J, Labadie K, Logares R, Sunagawa S, de Berardinis V, Salanoubat M, Dimier C, Kandels-Lewis S, Picheral M, Searson S, Tara-Oceans-Coordinators , Pesant S, Poulton N, Stepanauskas R, Bork P, Bowler C, Hingamp P, Sullivan MB, Iudicone D, Massana R, Aury JM, Henrissat B, Karsenti E, Jaillon O, Sieracki M, De Vargas C, Wincker P
2018 Jan 22; 9(1): 310. PubMed: 29358710.
Abstract + PDFSingle-celled eukaryotes (protists) are critical players in global biogeochemical cycling of nutrients and energy in the oceans. While their roles as primary producers and grazers are well appreciated, other aspects of their life histories remain obscure due to challenges in culturing and sequencing their natural diversity. Here, we exploit single-cell genomics and metagenomics data from the circumglobal Tara Oceans expedition to analyze the genome content and apparent oceanic distribution of seven prevalent lineages of uncultured heterotrophic stramenopiles. Based on the available data, each sequenced genome or genotype appears to have a specific oceanic distribution, principally correlated with water temperature and depth. The genome content provides hypotheses for specialization in terms of cell motility, food spectra, and trophic stages, including the potential impact on their lifestyles of horizontal gene transfer from prokaryotes. Our results support the idea that prominent heterotrophic marine protists perform diverse functions in ocean ecology.
568.
Nutritional preferences of human gut bacteria reveal their metabolic idiosyncrasies.
Tramontano M, Andrejev S, Pruteanu M, Klünemann M, Kuhn M, Galardini M, Jouhten P, Zelezniak A, Zeller G, Bork P, Typas A, Patil KR
2018 Apr 19; 3(4): 514-522. PubMed: 29556107.
Abstract + PDFBacterial metabolism plays a fundamental role in gut microbiota ecology and host-microbiome interactions. Yet the metabolic capabilities of most gut bacteria have remained unknown. Here we report growth characteristics of 96 phylogenetically diverse gut bacterial strains across 4 rich and 15 defined media. The vast majority of strains (76) grow in at least one defined medium, enabling accurate assessment of their biosynthetic capabilities. These do not necessarily match phylogenetic similarity, thus indicating a complex evolution of nutritional preferences. We identify mucin utilizers and species inhibited by amino acids and short-chain fatty acids. Our analysis also uncovers media for in vitro studies wherein growth capacity correlates well with in vivo abundance. Further value of the underlying resource is demonstrated by correcting pathway gaps in available genome-scale metabolic models of gut microorganisms. Together, the media resource and the extracted knowledge on growth abilities widen experimental and computational access to the gut microbiota.
2017 25 publication(s).
567.
Viral to metazoan marine plankton nucleotide sequences from the Tara Oceans expedition.
Alberti A, Poulain J, Engelen S, Labadie K, Romac S, Ferrera I, Albini G, Aury JM, Belser C, Bertrand A, Cruaud C, Da Silva C, Dossat C, Gavory F, Gas S, Guy J, Haquelle M, Jacoby E, Jaillon O, Lemainque A, Pelletier E, Samson G, Wessner M, Genoscope Technical Team , Acinas SG, Royo-Llonch M, Cornejo-Castillo FM, Logares R, Fernández-Gómez B, Bowler C, Cochrane G, Amid C, Hoopen PT, De Vargas C, Grimsley N, Desgranges E, Kandels-Lewis S, Ogata H, Poulton N, Sieracki ME, Stepanauskas R, Sullivan MB, Brum JR, Duhaime MB, Poulos BT, Hurwitz BL, Tara Oceans Consortium Coordinators , Pesant S, Karsenti E, Wincker P, Collaborators , Bazire P, Beluche O, Bertrand L, Besnard-Gonnet M, Bordelais I, Boutard M, Dubois M, Dumont C, Ettedgui E, Fernandez P, Garcia E, Aiach NG, Guerin T, Hamon C, Brun E, Lebled S, Lenoble P, Louesse C, Mahieu E, Mairey B, Martins N, Megret C, Milani C, Muanga J, Orvain C, Payen E, Perroud P, Petit E, Robert D, Ronsin M, Vacherie B, Acinas SG, Bork P, Boss E, Bowler C, De Vargas C, Follows M, Gorsky G, Grimsley N, Hingamp P, Iudicone D, Jaillon O, Kandels-Lewis S, Karp-Boss L, Karsenti E, Not F, Ogata H, Pesant S, Raes J, Sardet C, Sieracki ME, Speich S, Stemmann L, Sullivan MB, Sunagawa S, Wincker P.
Abstract + PDFA unique collection of oceanic samples was gathered by the Tara Oceans expeditions (2009-2013), targeting plankton organisms ranging from viruses to metazoans, and providing rich environmental context measurements. Thanks to recent advances in the field of genomics, extensive sequencing has been performed for a deep genomic analysis of this huge collection of samples. A strategy based on different approaches, such as metabarcoding, metagenomics, single-cell genomics and metatranscriptomics, has been chosen for analysis of size-fractionated plankton communities. Here, we provide detailed procedures applied for genomic data generation, from nucleic acids extraction to sequence production, and we describe registries of genomics datasets available at the European Nucleotide Archive (ENA, www.ebi.ac.uk/ena). The association of these metadata to the experimental procedures applied for their generation will help the scientific community to access these data and facilitate their analysis. This paper complements other efforts to provide a full description of experiments and open science resources generated from the Tara Oceans project, further extending their value for the study of the world's planktonic ecosystems.
566.
Functional implications of microbial and viral gut metagenome changes in early stage L-DOPA-naïve Parkinson's disease patients.
2017 Apr 28; 9(1): 39. PubMed: 28449715.
Abstract + PDFParkinson's disease (PD) presently is conceptualized as a protein aggregation disease in which pathology involves both the enteric and the central nervous system, possibly spreading from one to another via the vagus nerves. As gastrointestinal dysfunction often precedes or parallels motor symptoms, the enteric system with its vast diversity of microorganisms may be involved in PD pathogenesis. Alterations in the enteric microbial taxonomic level of L-DOPA-naïve PD patients might also serve as a biomarker.
565.
Erratum to: Functional implications of microbial and viral gut metagenome changes in early stage L-DOPA-naïve Parkinson's disease patients.
2017 Jun 29; 9(1): 61. PubMed: 28662719.
PDF564.
Systematic identification of phosphorylation-mediated protein interaction switches.
Betts MJ, Wichmann O, Utz M, Andre T, Petsalaki E, Minguez P, Parca L, Roth FP, Gavin AC, Bork P, Russell RB
2017 Mar 27; 13(3): e1005462. PubMed: 28346509.
Abstract + PDFProteomics techniques can identify thousands of phosphorylation sites in a single experiment, the majority of which are new and lack precise information about function or molecular mechanism. Here we present a fast method to predict potential phosphorylation switches by mapping phosphorylation sites to protein-protein interactions of known structure and analysing the properties of the protein interface. We predict 1024 sites that could potentially enable or disable particular interactions. We tested a selection of these switches and showed that phosphomimetic mutations indeed affect interactions. We estimate that there are likely thousands of phosphorylation mediated switches yet to be uncovered, even among existing phosphorylation datasets. The results suggest that phosphorylation sites on globular, as distinct from disordered, parts of the proteome frequently function as switches, which might be one of the ancient roles for kinase phosphorylation.
563.
Minimum information about a single amplified genome (MISAG) and a metagenome-assembled genome (MIMAG) of bacteria and archaea.
Bowers RM, Kyrpides NC, Stepanauskas R, Harmon-Smith M, Doud D, Reddy TBK, Schulz F, Jarett J, Rivers AR, Eloe-Fadrosh EA, Tringe SG, Ivanova NN, Copeland A, Clum A, Becraft ED, Malmstrom RR, Birren B, Podar M, Bork P, Weinstock GM, Garrity GM, Dodsworth JA, Yooseph S, Sutton G, Glöckner FO, Gilbert JA, Nelson WC, Hallam SJ, Jungbluth SP, Ettema TJG, Tighe S, Konstantinidis KT, Liu WT, Baker BJ, Rattei T, Eisen JA, Hedlund B, McMahon KD, Fierer N, Knight R, Finn R, Cochrane G, Karsch-Mizrachi I, Tyson GW, Rinke C
2017 Aug 8; 35(8): 725-731. PubMed: 28787424.
Abstract + PDFWe present two standards developed by the Genomic Standards Consortium (GSC) for reporting bacterial and archaeal genome sequences. Both are extensions of the Minimum Information about Any (x) Sequence (MIxS). The standards are the Minimum Information about a Single Amplified Genome (MISAG) and the Minimum Information about a Metagenome-Assembled Genome (MIMAG), including, but not limited to, assembly quality, and estimates of genome completeness and contamination. These standards can be used in combination with other GSC checklists, including the Minimum Information about a Genome Sequence (MIGS), Minimum Information about a Metagenomic Sequence (MIMS), and Minimum Information about a Marker Gene Sequence (MIMARKS). Community-wide adoption of MISAG and MIMAG will facilitate more robust comparative genomic analyses of bacterial and archaeal diversity.
562.
OGEE v2: an update of the online gene essentiality database with special focus on differentially essential genes in human cancer cell lines.
2017 Jan 4; 45(D1): D940-D944. PubMed: 27799467.
Abstract + PDFOGEE is an Online GEne Essentiality database. To enhance our understanding of the essentiality of genes, in OGEE we collected experimentally tested essential and non-essential genes, as well as associated gene properties known to contribute to gene essentiality. We focus on large-scale experiments, and complement our data with text-mining results. We organized tested genes into data sets according to their sources, and tagged those with variable essentiality statuses across data sets as conditionally essential genes, intending to highlight the complex interplay between gene functions and environments/experimental perturbations. Developments since the last public release include increased numbers of species and gene essentiality data sets, inclusion of non-coding essential sequences and genes with intermediate essentiality statuses. In addition, we included 16 essentiality data sets from cancer cell lines, corresponding to 9 human cancers; with OGEE, users can easily explore the shared and differentially essential genes within and between cancer types. These genes, especially those derived from cell lines that are similar to tumor samples, could reveal the oncogenic drivers, paralogous gene expression pattern and chromosomal structure of the corresponding cancer types, and can be further screened to identify targets for cancer therapy and/or new drug development. OGEE is freely available at http://ogee.medgenius.info.
561.
Quantitative 3D-imaging for cell biology and ecology of environmental microbial eukaryotes.
Abstract + PDFWe present a 3D-fluorescence imaging and classification tool for high throughput analysis of microbial eukaryotes in environmental samples. It entails high-content feature extraction that permits accurate automated taxonomic classification and quantitative data about organism ultrastructures and interactions. Using plankton samples from the Tara Oceans expeditions, we validate its applicability to taxonomic profiling and ecosystem analyses, and discuss its potential for future integration of eukaryotic cell biology into evolutionary and ecological studies.
560.
Subspecies in the global human gut microbiome.
Costea PI, Coelho LP, Sunagawa S, Munch R, Huerta-Cepas J, Forslund K, Hildebrand F, Kushugulova A, Zeller G, Bork P
2017 Dec 14; 13(12): 960. PubMed: 29242367.
Abstract + PDFPopulation genomics of prokaryotes has been studied in depth in only a small number of primarily pathogenic bacteria, as genome sequences of isolates of diverse origin are lacking for most species. Here, we conducted a large-scale survey of population structure in prevalent human gut microbial species, sampled from their natural environment, with a culture-independent metagenomic approach. We examined the variation landscape of 71 species in 2,144 human fecal metagenomes and found that in 44 of these, accounting for 72% of the total assigned microbial abundance, single-nucleotide variation clearly indicates the existence of sub-populations (here termed subspecies). A single subspecies (per species) usually dominates within each host, as expected from ecological theory. At the global scale, geographic distributions of subspecies differ between phyla, with Firmicutes subspecies being significantly more geographically restricted. To investigate the functional significance of the delineated subspecies, we identified genes that consistently distinguish them in a manner that is independent of reference genomes. We further associated these subspecies-specific genes with properties of the microbial community and the host. For example, two of the three Eubacterium rectale subspecies consistently harbor an accessory pro-inflammatory flagellum operon that is associated with lower gut community diversity, higher host BMI, and higher blood fasting insulin levels. Using an additional 676 human oral samples, we further demonstrate the existence of niche specialized subspecies in the different parts of the oral cavity. Taken together, we provide evidence for subspecies in the majority of abundant gut prokaryotes, leading to a better functional and ecological understanding of the human gut microbiome in conjunction with its host.
559.
metaSNV: A tool for metagenomic strain level analysis.
Abstract + PDFWe present metaSNV, a tool for single nucleotide variant (SNV) analysis in metagenomic samples, capable of comparing populations of thousands of bacterial and archaeal species. The tool uses as input nucleotide sequence alignments to reference genomes in standard SAM/BAM format, performs SNV calling for individual samples and across the whole data set, and generates various statistics for individual species including allele frequencies and nucleotide diversity per sample as well as distances and fixation indices across samples. Using published data from 676 metagenomic samples of different sites in the oral cavity, we show that the results of metaSNV are comparable to those of MIDAS, an alternative implementation for metagenomic SNV analysis, while data processing is faster and has a smaller storage footprint. Moreover, we implement a set of distance measures that allow the comparison of genomic variation across metagenomic samples and delineate sample-specific variants to enable the tracking of specific strain populations over time. The implementation of metaSNV is available at: http://metasnv.embl.de/.
558.
Towards standards for human fecal sample processing in metagenomic studies.
Costea PI, Zeller G, Sunagawa S, Pelletier E, Alberti A, Levenez F, Tramontano M, Driessen M, Hercog R, Jung FE, Kultima JR, Hayward MR, Coelho LP, Allen-Vercoe E, Bertrand L, Blaut M, Brown JRM, Carton T, Cools-Portier S, Daigneault M, Derrien M, Druesne A, de Vos WM, Finlay BB, Flint HJ, Guarner F, Hattori M, Heilig H, Luna RA, van Hylckama Vlieg J, Junick J, Klymiuk I, Langella P, Le Chatelier E, Mai V, Manichanh C, Martin JC, Mery C, Morita H, O'Toole PW, Orvain C, Patil KR, Penders J, Persson S, Pons N, Popova M, Salonen A, Saulnier D, Scott KP, Singh B, Slezak K, Veiga P, Versalovic J, Zhao L, Zoetendal EG, Ehrlich SD, Dore J, Bork P
2017 Nov 2; 35(11): 1069-1076. PubMed: 28967887.
Abstract + PDFTechnical variation in metagenomic analysis must be minimized to confidently assess the contributions of microbiota to human health. Here we tested 21 representative DNA extraction protocols on the same fecal samples and quantified differences in observed microbial community composition. We compared them with differences due to library preparation and sample storage, which we contrasted with observed biological variation within the same specimen or within an individual over time. We found that DNA extraction had the largest effect on the outcome of metagenomic analysis. To rank DNA extraction protocols, we considered resulting DNA quantity and quality, and we ascertained biases in estimates of community diversity and the ratio between Gram-positive and Gram-negative bacteria. We recommend a standardized DNA extraction method for human fecal samples, for which transferability across labs was established and which was further benchmarked using a mock community of known composition. Its adoption will improve comparability of human gut microbiome studies and facilitate meta-analyses.
557.
InterPro in 2017-beyond protein family and domain annotations.
Finn RD, Attwood TK, Babbitt PC, Bateman A, Bork P, Bridge AJ, Chang HY, Dosztányi Z, El-Gebali S, Fraser M, Gough J, Haft D, Holliday GL, Huang H, Huang X, Letunic I, Lopez R, Lu S, Marchler-Bauer A, Mi H, Mistry J, Natale DA, Necci M, Nuka G, Orengo CA, Park Y, Pesseat S, Piovesan D, Potter SC, Rawlings ND, Redaschi N, Richardson L, Rivoire C, Sangrador-Vegas A, Sigrist C, Sillitoe I, Smithers B, Squizzato S, Sutton G, Thanki N, Thomas PD, Tosatto SC, Wu CH, Xenarios I, Yeh LS, Young SY, Mitchell AL
2017 Jan 4; 45(D1): D190-D199. PubMed: 27899635.
Abstract + PDFInterPro (http://www.ebi.ac.uk/interpro/) is a freely available database used to classify protein sequences into families and to predict the presence of important domains and sites. InterProScan is the underlying software that allows both protein and nucleic acid sequences to be searched against InterPro's predictive models, which are provided by its member databases. Here, we report recent developments with InterPro and its associated software, including the addition of two new databases (SFLD and CDD), and the functionality to include residue-level annotation and prediction of intrinsic disorder. These developments enrich the annotations provided by InterPro, increase the overall number of residues annotated and allow more specific functional inferences.
556.
Corrigendum: Disentangling type 2 diabetes and metformin treatment signatures in the human gut microbiota.
Forslund K, Hildebrand F, Nielsen T, Falony G, Le Chatelier E, Sunagawa S, Prifti E, Vieira-Silva S, Gudmundsdottir V, Pedersen HK, Arumugam M, Kristiansen K, Voigt AY, Vestergaard H, Hercog R, Costea PI, Kultima JR, Li J, Jørgensen T, Levenez F, Dore J, MetaHit-Consortium , Nielsen HB, Brunak S, Raes J, Hansen T, Wang J, Ehrlich SD, Bork P, Pedersen O
PDF555.
Fast genome-wide functional annotation through orthology assignment by eggNOG-mapper.
2017 Aug 1; 34(8): 2115-2122. PubMed: 28460117.
Abstract + PDFOrthology assignment is ideally suited for functional inference. However, because predicting orthology is computationally intensive at large scale, and most pipelines are relatively inaccessible (e.g. new assignments only available through database updates), less precise homology-based functional transfer is still the default for (meta-)genome annotation. We therefore developed eggNOG-mapper, a tool for functional annotation of large sets of sequences based on fast orthology assignments using precomputed clusters and phylogenies from the eggNOG database. To validate our method, we benchmarked Gene Ontology predictions against two widely used homology-based approaches: BLAST and InterProScan. Orthology filters applied to BLAST results reduced the rate of false positive assignments by 11%, and increased the ratio of experimentally validated terms recovered over all terms assigned per protein by 15%. Compared to InterProScan, eggNOG-mapper achieved similar proteome coverage and precision while predicting, on average, 41 more terms per protein and increasing the rate of experimentally validated terms recovered over total term assignments per protein by 35%. EggNOG-mapper predictions scored within the top-5 methods in the three Gene Ontology categories using the CAFA2 NK-partial benchmark. Finally, we evaluated eggNOG-mapper for functional annotation of metagenomics data, yielding better performance than interProScan. eggNOG-mapper runs ∼15x faster than BLAST and at least 2.5x faster than InterProScan. The tool is available standalone and as an online service at http://eggnog-mapper.embl.de.
554.
Metabolic anchor reactions for robust biorefining.
Jouhten P, Huerta-Cepas J, Bork P, Patil KR
Abstract + PDFMicrobial cell factories based on renewable carbon sources are fundamental to a sustainable bio-economy. The economic feasibility of producer cells requires robust performance balancing growth and production. However, the inherent competition between these two objectives often leads to instability and reduces productivity. While algorithms exist to design metabolic network reduction strategies for aligning these objectives, the biochemical basis of the growth-product coupling has remained unresolved. Here, we reveal key reactions in the cellular biochemical repertoire as universal anchor reactions for aligning cell growth and production. A necessary condition for a reaction to be an anchor is that it splits a substrate into two or more molecules. By searching the currently known biochemical reaction space, we identify 62 C-C cleaving anchor reactions, such as isocitrate lyase (EC 4.1.3.1) and L-tryptophan indole-lyase (EC 4.1.99.1), which are relevant for biorefining. The here identified anchor reactions mark network nodes for basing growth-coupled metabolic engineering and novel pathway designs.
553.
The microbiomes of blowflies and houseflies as bacterial transmission reservoirs.
Junqueira ACM, Ratan A, Acerbi E, Drautz-Moses DI, Premkrishnan BNV, Costea PI, Linz B, Purbojati RW, Paulo DF, Gaultier NE, Subramanian P, Hasan NA, Colwell RR, Bork P, Azeredo-Espin AML, Bryant DA, Schuster SC
Abstract + PDFBlowflies and houseflies are mechanical vectors inhabiting synanthropic environments around the world. They feed and breed in fecal and decaying organic matter, but the microbiome they harbour and transport is largely uncharacterized. We sampled 116 individual houseflies and blowflies from varying habitats on three continents and subjected them to high-coverage, whole-genome shotgun sequencing. This allowed for genomic and metagenomic analyses of the host-associated microbiome at the species level. Both fly host species segregate based on principal coordinate analysis of their microbial communities, but they also show an overlapping core microbiome. Legs and wings displayed the largest microbial diversity and were shown to be an important route for microbial dispersion. The environmental sequencing approach presented here detected a stochastic distribution of human pathogens, such as Helicobacter pylori, thereby demonstrating the potential of flies as proxies for environmental and public health surveillance.
552.
Capturing protein communities by structural proteomics in a thermophilic eukaryote.
Kastritis PL, O'Reilly FJ, Bock T, Li YY, Rogon MZ, Buczak K, Romanov N, Betts MJ, Bui KH, Hagen WJ, Hennrich ML, Mackmull MT, Rappsilber J, Russell RB, Bork P, Beck M, Gavin AC
2017 Jul 25; 13(7): 936. PubMed: 28743795.
Abstract + PDFThe arrangement of proteins into complexes is a key organizational principle for many cellular functions. Although the topology of many complexes has been systematically analyzed in isolation, their molecular sociology in situ remains elusive. Here, we show that crude cellular extracts of a eukaryotic thermophile, Chaetomium thermophilum, retain basic principles of cellular organization. Using a structural proteomics approach, we simultaneously characterized the abundance, interactions, and structure of a third of the C. thermophilum proteome within these extracts. We identified 27 distinct protein communities that include 108 interconnected complexes, which dynamically associate with each other and functionally benefit from being in close proximity in the cell. Furthermore, we investigated the structure of fatty acid synthase within these extracts by cryoEM and this revealed multiple, flexible states of the enzyme in adaptation to its association with other complexes, thus exemplifying the need for in situ studies. As the components of the captured protein communities are known-at both the protein and complex levels-this study constitutes another step forward toward a molecular understanding of subcellular organization.
551.
Pole-to-Pole Connections: Similarities between Arctic and Antarctic Microbiomes and Their Vulnerability to Environmental Change
Kleinteich J, Hildebrand F, Bahram M, Voigt AY, Wood SA, Jungblut AD, Küpper FC, Quesada A, Camacho A, Pearce DA, Convey P, Vincent WF, Zarfl C, Bork P, Dietrich DR
2017 Nov 10; 5: 1-11. PID: 725.
Abstract + PDFThe global biogeography of microorganisms remains poorly resolved, which limits the current understanding of microbial resilience toward environmental changes. Using high-throughput 16S rRNA gene amplicon sequencing, we characterized the microbial diversity of terrestrial and lacustrine biofilms from the Arctic, Antarctic and temperate regions. Our analyses suggest that bacterial community compositions at the poles are more similar to each other than they are to geographically closer temperate habitats, with 32% of all operational taxonomic units (OTUs) co-occurring in both polar regions. While specific microbial taxa were confined to distinct regions, representing potentially endemic populations, the percentage of cosmopolitan taxa was higher in Arctic (43%) than in Antarctic samples (36%). The overlap in polar microbial OTUs may be explained by natural or anthropogenically-mediated dispersal in combination with environmental filtering. Current and future changing environmental conditions may enhance microbial invasion, establishment of cosmopolitan genotypes and loss of endemic taxa.
550.
Gut microbiota differs between children with Inflammatory Bowel Disease and healthy siblings in taxonomic and functional composition - a metagenomic analysis.
2017 Apr 1; 312(4): G327-G339. PubMed: 28039159.
Abstract + PDFCurrent treatment for pediatric IBD patients is often ineffective, with serious side effects. Manipulating the gut microbiota via fecal microbiota transplantation (FMT) is an emerging treatment approach but remains controversial. We aimed to assess the composition of the fecal microbiome through a comparison of pediatric IBD patients to their healthy siblings, evaluating risks and prospects for FMT in this setting. A Case-Control (Sibling) Study was conducted analyzing fecal samples of six children with Crohn's Disease (CD), six children with Ulcerative Colitis (UC) and 12 healthy siblings by metagenomic sequencing. In addition, lifetime antibiotic intake was retrospectively determined. Species richness and diversity were significantly reduced in UC patients compared to control (MWU FDR = 0.011). In UC, bacteria positively influencing gut homeostasis e.g. Eubacterium rectale and Faecalibacterium prausnitzii were significantly reduced in abundance (MWU FDR = 0.05). Known pathobionts like Escherichia coli were enriched in UC patients (MWU FDR = 0.084). Moreover, E. coli abundance correlated positively with that of several virulence genes (SCC > 0.65, FDR < 0.1). A shift towards antibiotic resistant taxa in both IBD groups distinguished them from controls (MWU BY FDR = 0.062 in UC, MWU BY FDR = 0.019 in CD). The collected results confirm a microbial dysbiosis in pediatric UC, and to a lesser extent in CD patients, replicating associations found previously using different methods. Taken together, these observations suggest microbiotal remodeling therapy from family donors, at least for children with UC, as a viable option.
549.
proGenomes: a resource for consistent functional and taxonomic annotations of prokaryotic genomes.
2017 Jan 4; 45(D1): D529-D534. PubMed: 28053165.
Abstract + PDFThe availability of microbial genomes has opened many new avenues of research within microbiology. This has been driven primarily by comparative genomics approaches, which rely on accurate and consistent characterization of genomic sequences. It is nevertheless difficult to obtain consistent taxonomic and integrated functional annotations for defined prokaryotic clades. Thus, we developed proGenomes, a resource that provides user-friendly access to currently 25 038 high-quality genomes whose sequences and consistent annotations can be retrieved individually or by taxonomic clade. These genomes are assigned to 5306 consistent and accurate taxonomic species clusters based on previously established methodology. proGenomes also contains functional information for almost 80 million protein-coding genes, including a comprehensive set of general annotations and more focused annotations for carbohydrate-active enzymes and antibiotic resistance genes. Additionally, broad habitat information is provided for many genomes. All genomes and associated information can be downloaded by user-selected clade or multiple habitat-specific sets of representative genomes. We expect that the availability of high-quality genomes with comprehensive functional annotations will promote advances in clinical microbial genomics, functional evolution and other subfields of microbiology. proGenomes is available at http://progenomes.embl.de.
548.
Bioinformatics Analysis of Functional Associations of PTMs.
Minguez P, Bork P
2017; 1558: 303-320. PubMed: 28150244.
Abstract + PDFPost-translational modifications (PTMs) are an important source of protein regulation; they fine-tune the function, localization, and interaction with other molecules of the majority of proteins and are partially responsible for their multifunctionality. Usually, proteins have several potential modification sites, and their patterns of occupancy are associated with certain functional states. These patterns imply cross talk among PTMs within and between proteins, the majority of which are still to be discovered. Several methods detect associations between PTMs; these have recently combined into a global resource, the PTMcode database, which contains already known and predicted functional associations between pairs of PTMs from more than 45,000 proteins in 19 eukaryotic species.
547.
RTK: efficient rarefaction analysis of large datasets.
2017 Aug 15; 33(16): 2594-2595. PubMed: 28398468.
Abstract + PDFThe rapidly expanding microbiomics field is generating increasingly larger datasets, characterizing the microbiota in diverse environments. Although classical numerical ecology methods provide a robust statistical framework for their analysis, software currently available is inadequate for large datasets and some computationally intensive tasks, like rarefaction and associated analysis.
546.
The STRING database in 2017: quality-controlled protein-protein association networks, made broadly accessible.
Szklarczyk D, Morris JH, Cook H, Kuhn M, Wyder S, Simonovic M, Santos A, Doncheva NT, Roth A, Bork P, Jensen LJ, von Mering C
2017 Jan 4; 45(D1): D362-D368. PubMed: 27924014.
Abstract + PDFA system-wide understanding of cellular function requires knowledge of all functional interactions between the expressed proteins. The STRING database aims to collect and integrate this information, by consolidating known and predicted protein-protein association data for a large number of organisms. The associations in STRING include direct (physical) interactions, as well as indirect (functional) interactions, as long as both are specific and biologically meaningful. Apart from collecting and reassessing available experimental data on protein-protein interactions, and importing known pathways and protein complexes from curated databases, interaction predictions are derived from the following sources: (i) systematic co-expression analysis, (ii) detection of shared selective signals across genomes, (iii) automated text-mining of the scientific literature and (iv) computational transfer of interaction knowledge between organisms based on gene orthology. In the latest version 10.5 of STRING, the biggest changes are concerned with data dissemination: the web frontend has been completely redesigned to reduce dependency on outdated browser technologies, and the database can now also be queried from inside the popular Cytoscape software framework. Further improvements include automated background analysis of user inputs for functional enrichments, and streamlined download options. The STRING resource is available online, at http://string-db.org/.
545.
[Microbial Biomarkers for Early Cancer Detection].
2017 Feb; 142(4): 267-274. PubMed: 28235227.
Abstract + PDFThe human microbiome - the vast amount of microbes that colonize our body - play an important role in maintaining our health. Changes in microbiome composition have been linked to multiple diseases including cancer. Although mechanisms and causalities of these associations still have to be uncovered, microbiome alterations across various stages of disease can be utilized for novel diagnostic and prognostic tests. Research on biomarkers extracted from the gut microbiome has in particular focused on colorectal cancer, where clinical use is already on the horizon. For example, multiple microbial taxonomic markers such as Fusobacterium nucleatum and other oral pathogens have been identified in human feces with potential for non-invasive diagnostics and prognostics. The article summarizes the recent developments, but also limitations and challenges for the development of microbiome-based biomarkers for cancer early detection.
544.
GEAR: A database of Genomic Elements Associated with drug Resistance.
Abstract + PDFDrug resistance is becoming a serious problem that leads to the failure of standard treatments, which is generally developed because of genetic mutations of certain molecules. Here, we present GEAR (A database of Genomic Elements Associated with drug Resistance) that aims to provide comprehensive information about genomic elements (including genes, single-nucleotide polymorphisms and microRNAs) that are responsible for drug resistance. Right now, GEAR contains 1631 associations between 201 human drugs and 758 genes, 106 associations between 29 human drugs and 66 miRNAs, and 44 associations between 17 human drugs and 22 SNPs. These relationships are firstly extracted from primary literature with text mining and then manually curated. The drug resistome deposited in GEAR provides insights into the genetic factors underlying drug resistance. In addition, new indications and potential drug combinations can be identified based on the resistome. The GEAR database can be freely accessed through http://gear.comp-sysbio.org.
543.
Salt-responsive gut commensal modulates TH17 axis and disease.
Wilck N, Matus MG, Kearney SM, Olesen SW, Forslund K, Bartolomaeus H, Haase S, Mähler A, Balogh A, Markó L, Vvedenskaya O, Kleiner FH, Tsvetkov D, Klug L, Costea PI, Sunagawa S, Maier L, Rakova N, Schatz V, Neubert P, Frätzer C, Krannich A, Gollasch M, Grohme DA, Côrte-Real BF, Gerlach RG, Basic M, Typas A, Wu C, Titze JM, Jantsch J, Boschmann M, Dechend R, Kleinewietfeld M, Kempa S, Bork P, Linker RA, Alm EJ, Müller DN
Abstract + PDFA Western lifestyle with high salt consumption can lead to hypertension and cardiovascular disease. High salt may additionally drive autoimmunity by inducing T helper 17 (TH17) cells, which can also contribute to hypertension. Induction of TH17 cells depends on gut microbiota; however, the effect of salt on the gut microbiome is unknown. Here we show that high salt intake affects the gut microbiome in mice, particularly by depleting Lactobacillus murinus. Consequently, treatment of mice with L. murinus prevented salt-induced aggravation of actively induced experimental autoimmune encephalomyelitis and salt-sensitive hypertension by modulating TH17 cells. In line with these findings, a moderate high-salt challenge in a pilot study in humans reduced intestinal survival of Lactobacillus spp., increased TH17 cells and increased blood pressure. Our results connect high salt intake to the gut-immune axis and highlight the gut microbiome as a potential therapeutic target to counteract salt-sensitive conditions.
2016 26 publication(s).
542.
Standardized benchmarking in the quest for orthologs.
Altenhoff AM, Boeckmann B, Capella-Gutierrez S, Dalquen DA, DeLuca T, Forslund K, Huerta-Cepas J, Linard B, Pereira C, Pryszcz LP, Schreiber F, da Silva AS, Szklarczyk D, Train CM, Bork P, Lecompte O, von Mering C, Xenarios I, Sjölander K, Jensen LJ, Martin MJ, Muffato M
2016 May 4; 13(5): 425-30. Epub 2016 Apr 4; PubMed: 27043882.
Abstract + PDFAchieving high accuracy in orthology inference is essential for many comparative, evolutionary and functional genomic analyses, yet the true evolutionary history of genes is generally unknown and orthologs are used for very different applications across phyla, requiring different precision-recall trade-offs. As a result, it is difficult to assess the performance of orthology inference methods. Here, we present a community effort to establish standards and an automated web-based service to facilitate orthology benchmarking. Using this service, we characterize 15 well-established inference methods and resources on a battery of 20 different benchmarks. Standardized benchmarking provides a way for users to identify the most effective methods for the problem at hand, sets a minimum requirement for new tools and resources, and guides the development of more accurate orthology inference methods.
541.
Energy efficiency trade-offs drive nucleotide usage in transcribed regions.
2016 Apr 21; 7: 11334. PubMed: 27098217.
Abstract + PDFEfficient nutrient usage is a trait under universal selection. A substantial part of cellular resources is spent on making nucleotides. We thus expect preferential use of cheaper nucleotides especially in transcribed sequences, which are often amplified thousand-fold compared with genomic sequences. To test this hypothesis, we derive a mutation-selection-drift equilibrium model for nucleotide skews (strand-specific usage of 'A' versus 'T' and 'G' versus 'C'), which explains nucleotide skews across 1,550 prokaryotic genomes as a consequence of selection on efficient resource usage. Transcription-related selection generally favours the cheaper nucleotides 'U' and 'C' at synonymous sites. However, the information encoded in mRNA is further amplified through translation. Due to unexpected trade-offs in the codon table, cheaper nucleotides encode on average energetically more expensive amino acids. These trade-offs apply to both strand-specific nucleotide usage and GC content, causing a universal bias towards the more expensive nucleotides 'A' and 'G' at non-synonymous coding sites.
540.
Integration of multi-omics data of a genome-reduced bacterium: Prevalence of post-transcriptional regulation and its correlation with protein abundances.
Chen WH, van Noort V, Lluch-Senar M, Hennrich ML, H Wodke JA, Yus E, Alibés A, Roma G, Mende DR, Pesavento C, Typas A, Gavin AC, Serrano L, Bork P
2016 Feb 18; 44(3): 1192-202. Epub 2016 Jan 14; PubMed: 26773059.
Abstract + PDFWe developed a comprehensive resource for the genome-reduced bacterium Mycoplasma pneumoniae comprising 1748 consistently generated '-omics' data sets, and used it to quantify the power of antisense non-coding RNAs (ncRNAs), lysine acetylation, and protein phosphorylation in predicting protein abundance (11%, 24% and 8%, respectively). These factors taken together are four times more predictive of the proteome abundance than of mRNA abundance. In bacteria, post-translational modifications (PTMs) and ncRNA transcription were both found to increase with decreasing genomic GC-content and genome size. Thus, the evolutionary forces constraining genome size and GC-content modify the relative contributions of the different regulatory layers to proteome homeostasis, and impact more genomic and genetic features than previously appreciated. Indeed, these scaling principles will enable us to develop more informed approaches when engineering minimal synthetic genomes.
539.
Cyanobacterial symbionts diverged in the late Cretaceous towards lineage-specific nitrogen fixation factories in single-celled phytoplankton.
Cornejo-Castillo FM, Cabello AM, Salazar G, Sánchez-Baracaldo P, Lima-Mendez G, Hingamp P, Alberti A, Sunagawa S, Bork P, De Vargas C, Raes J, Bowler C, Wincker P, Zehr JP, Gasol JM, Massana R, Acinas SG
2016 Mar 22; 7: 11071. PubMed: 27002549.
Abstract + PDFThe unicellular cyanobacterium UCYN-A, one of the major contributors to nitrogen fixation in the open ocean, lives in symbiosis with single-celled phytoplankton. UCYN-A includes several closely related lineages whose partner fidelity, genome-wide expression and time of evolutionary divergence remain to be resolved. Here we detect and distinguish UCYN-A1 and UCYN-A2 lineages in symbiosis with two distinct prymnesiophyte partners in the South Atlantic Ocean. Both symbiotic systems are lineage specific and differ in the number of UCYN-A cells involved. Our analyses infer a streamlined genome expression towards nitrogen fixation in both UCYN-A lineages. Comparative genomics reveal a strong purifying selection in UCYN-A1 and UCYN-A2 with a diversification process ∼91 Myr ago, in the late Cretaceous, after the low-nutrient regime period occurred during the Jurassic. These findings suggest that UCYN-A diversified in a co-evolutionary process, wherein their prymnesiophyte partners acted as a barrier driving an allopatric speciation of extant UCYN-A lineages.
538.
CART - a chemical annotation retrieval toolkit.
2016 Sep 15; 32(18): 2869-71. Epub 2016 Jun 2; PubMed: 27256313.
Abstract + PDFData on bioactivities of drug-like chemicals is rapidly accumulating in public repositories, creating new opportunities for research in computational systems pharmacology. However, integrative analysis of these data sets is difficult due to prevailing ambiguity between chemical names and identifiers and a lack of cross-references between databases.
537.
Plankton networks driving carbon export in the oligotrophic ocean.
Guidi L, Chaffron S, Bittner L, Eveillard D, Larhlimi A, Roux S, Darzi Y, Audic S, Berline L, Brum J, Coelho LP, Espinoza JC, Malviya S, Sunagawa S, Dimier C, Kandels-Lewis S, Picheral M, Poulain J, Searson S, Stemmann L, Not F, Hingamp P, Speich S, Follows M, Karp-Boss L, Boss E, Ogata H, Pesant S, Weissenbach J, Wincker P, Acinas SG, Bork P, De Vargas C, Iudicone D, Sullivan MB, Raes J, Karsenti E, Bowler C, Gorsky G.
Abstract + PDFThe biological carbon pump is the process by which CO2 is transformed to organic carbon via photosynthesis, exported through sinking particles, and finally sequestered in the deep ocean. While the intensity of the pump correlates with plankton community composition, the underlying ecosystem structure driving the process remains largely uncharacterized. Here we use environmental and metagenomic data gathered during the Tara Oceans expedition to improve our understanding of carbon export in the oligotrophic ocean. We show that specific plankton communities, from the surface and deep chlorophyll maximum, correlate with carbon export at 150 m and highlight unexpected taxa such as Radiolaria and alveolate parasites, as well as Synechococcus and their phages, as lineages most strongly associated with carbon export in the subtropical, nutrient-depleted, oligotrophic ocean. Additionally, we show that the relative abundance of a few bacterial and viral genes can predict a significant fraction of the variability in carbon export in these regions.
536.
ETE 3: Reconstruction, analysis and visualization of phylogenomic data.
Huerta-Cepas J, Serra F, Bork P
2016 Jun 26; 33(6): 1635-8. Epub 2016 Feb 26; PubMed: 26921390.
Abstract + PDFThe Environment for Tree Exploration (ETE) is a computational framework that simplifies the reconstruction, analysis and visualization of phylogenetic trees and multiple sequence alignments. Here we present ETE v3, featuring numerous improvements in the underlying library of methods, and providing a novel set of standalone tools to perform common tasks in comparative genomics and phylogenetics. The new features include i) building gene-based and supermatrix-based phylogenies using a single command, ii) testing and visualizing evolutionary models, iii) calculating distances between trees of different size or including duplications, and iv) providing seamless integration with the NCBI taxonomy database. ETE is freely available at http://etetoolkit.org.
535.
eggNOG 4.5: a hierarchical orthology framework with improved functional annotations for eukaryotic, prokaryotic and viral sequences.
Huerta-Cepas J, Szklarczyk D, Forslund K, Cook H, Heller D, Walter MC, Rattei T, Mende DR, Sunagawa S, Kuhn M, Jensen LJ, von Mering C, Bork P
2016 Jan 4; 44: D286-93. Epub 2015 Nov 17; PubMed: 26582926.
Abstract + PDFeggNOG is a public resource that provides Orthologous Groups (OGs) of proteins at different taxonomic levels, each with integrated and summarized functional annotations. Developments since the latest public release include changes to the algorithm for creating OGs across taxonomic levels, making nested groups hierarchically consistent. This allows for a better propagation of functional terms across nested OGs and led to the novel annotation of 95 890 previously uncharacterized OGs, increasing overall annotation coverage from 67% to 72%. The functional annotations of OGs have been expanded to also provide Gene Ontology terms, KEGG pathways and SMART/Pfam domains for each group. Moreover, eggNOG now provides pairwise orthology relationships within OGs based on analysis of phylogenetic trees. We have also incorporated a framework for quickly mapping novel sequences to OGs based on precomputed HMM profiles. Finally, eggNOG version 4.5 incorporates a novel data set spanning 2605 viral OGs, covering 5228 proteins from 352 viral proteomes. All data are accessible for bulk downloading, as a web-service, and through a completely redesigned web interface. The new access points provide faster searches and a number of new browsing and visualization capabilities, facilitating the needs of both experts and less experienced users. eggNOG v4.5 is available at http://eggnog.embl.de.
534.
Intestinal microbiome is related to lifetime antibiotic use in Finnish pre-school children.
2016 Jan 26; 7: 10410. PubMed: 26811868.
Abstract + PDFEarly-life antibiotic use is associated with increased risk for metabolic and immunological diseases, and mouse studies indicate a causal role of the disrupted microbiome. However, little is known about the impacts of antibiotics on the developing microbiome of children. Here we use phylogenetics, metagenomics and individual antibiotic purchase records to show that macrolide use in 2-7 year-old Finnish children (N=142; sampled at two time points) is associated with a long-lasting shift in microbiota composition and metabolism. The shift includes depletion of Actinobacteria, increase in Bacteroidetes and Proteobacteria, decrease in bile-salt hydrolase and increase in macrolide resistance. Furthermore, macrolide use in early life is associated with increased risk of asthma and predisposes to antibiotic-associated weight gain. Overweight and asthmatic children have distinct microbiota compositions. Penicillins leave a weaker mark on the microbiota than macrolides. Our results support the idea that, without compromising clinical practice, the impact on the intestinal microbiota should be considered when prescribing antibiotics.
533.
The SIDER database of drugs and side effects.
2016 Jan 4; 44: D1075-9. Epub 2015 Oct 19; PubMed: 26481350.
Abstract + PDFUnwanted side effects of drugs are a burden on patients and a severe impediment in the development of new drugs. At the same time, adverse drug reactions (ADRs) recorded during clinical trials are an important source of human phenotypic data. It is therefore essential to combine data on drugs, targets and side effects into a more complete picture of the therapeutic mechanism of actions of drugs and the ways in which they cause adverse reactions. To this end, we have created the SIDER ('Side Effect Resource', http://sideeffects.embl.de) database of drugs and ADRs. The current release, SIDER 4, contains data on 1430 drugs, 5880 ADRs and 140 064 drug-ADR pairs, which is an increase of 40% compared to the previous version. For more fine-grained analyses, we extracted the frequency with which side effects occur from the package inserts. This information is available for 39% of drug-ADR pairs, 19% of which can be compared to the frequency under placebo treatment. SIDER furthermore contains a data set of drug indications, extracted from the package inserts using Natural Language Processing. These drug indications are used to reduce the rate of false positives by identifying medical terms that do not correspond to ADRs.
532.
MOCAT2: a metagenomic assembly, annotation and profiling framework.
Kultima JR, Coelho LP, Forslund K, Huerta-Cepas J, Li SS, Driessen M, Voigt AY, Zeller G, Sunagawa S, Bork P
2016 Aug 15; 32(16): 2520-3. Epub 2016 Apr 8; PubMed: 27153620.
Abstract + PDFMOCAT2 is a software pipeline for metagenomic sequence assembly and gene prediction with novel features for taxonomic and functional abundance profiling. The automated generation and efficient annotation of non-redundant reference catalogs by propagating pre-computed assignments from 18 databases covering various functional categories allows for fast and comprehensive functional characterization of metagenomes.
531.
Interactive tree of life (iTOL) v3: an online tool for the display and annotation of phylogenetic and other trees.
Letunic I, Bork P
2016 Jul 8; 44: W242-5. Epub 2016 Apr 19; PubMed: 27095192.
Abstract + PDFInteractive Tree Of Life (http://itol.embl.de) is a web-based tool for the display, manipulation and annotation of phylogenetic trees. It is freely available and open to everyone. The current version was completely redesigned and rewritten, utilizing current web technologies for speedy and streamlined processing. Numerous new features were introduced and several new data types are now supported. Trees with up to 100,000 leaves can now be efficiently displayed. Full interactive control over precise positioning of various annotation features and an unlimited number of datasets allow the easy creation of complex tree visualizations. iTOL 3 is the first tool which supports direct visualization of the recently proposed phylogenetic placements format. Finally, iTOL's account system has been redesigned to simplify the management of trees in user-defined workspaces and projects, as it is heavily used and currently handles already more than 500,000 trees from more than 10,000 individual users.
530.
Durable coexistence of donor and recipient strains after fecal microbiota transplantation.
Li SS, Zhu A, Benes V, Costea PI, Hercog R, Hildebrand F, Huerta-Cepas J, Nieuwdorp M, Salojärvi J, Voigt AY, Zeller G, Sunagawa S, de Vos WM, Bork P
Abstract + PDFFecal microbiota transplantation (FMT) has shown efficacy in treating recurrent Clostridium difficile infection and is increasingly being applied to other gastrointestinal disorders, yet the fate of native and introduced microbial strains remains largely unknown. To quantify the extent of donor microbiota colonization, we monitored strain populations in fecal samples from a recent FMT study on metabolic syndrome patients using single-nucleotide variants in metagenomes. We found extensive coexistence of donor and recipient strains, persisting 3 months after treatment. Colonization success was greater for conspecific strains than for new species, the latter falling within fluctuation levels observed in healthy individuals over a similar time frame. Furthermore, same-donor recipients displayed varying degrees of microbiota transfer, indicating individual patterns of microbiome resistance and donor-recipient compatibilities.
529.
Bacterial antisense RNAs are mainly the product of transcriptional noise.
Lloréns-Rico V, Cano J, Kamminga T, Gil R, Latorre A, Chen WH, Bork P, Glass JI, Serrano L, Lluch-Senar M
2016 Mar; 2(3): e1501363. PubMed: 26973873.
Abstract + PDFcis-Encoded antisense RNAs (asRNAs) are widespread along bacterial transcriptomes. However, the role of most of these RNAs remains unknown, and there is an ongoing discussion as to what extent these transcripts are the result of transcriptional noise. We show, by comparative transcriptomics of 20 bacterial species and one chloroplast, that the number of asRNAs is exponentially dependent on the genomic AT content and that expression of asRNA at low levels exerts little impact in terms of energy consumption. A transcription model simulating mRNA and asRNA production indicates that the asRNA regulatory effect is only observed above certain expression thresholds, substantially higher than physiological transcript levels. These predictions were verified experimentally by overexpressing nine different asRNAs in Mycoplasma pneumoniae. Our results suggest that most of the antisense transcripts found in bacteria are the consequence of transcriptional noise, arising at spurious promoters throughout the genome.
528.
Gut Microbiota Linked to Sexual Preference and HIV Infection.
Noguera-Julian M, Rocafort M, Guillén Y, Rivera J, Casadellà M, Nowak P, Hildebrand F, Zeller G, Parera M, Bellido R, Rodríguez C, Carrillo J, Mothe B, Coll J, Bravo I, Estany C, Herrero C, Saz J, Sirera G, Torrela A, Navarro J, Crespo M, Brander C, Negredo E, Blanco J, Guarner F, Calle ML, Bork P, Sönnerborg A, Clotet B, Paredes R
2016 Mar; 5: 135-46. PubMed: 27077120.
Abstract + PDFThe precise effects of HIV-1 on the gut microbiome are unclear. Initial cross-sectional studies provided contradictory associations between microbial richness and HIV serostatus and suggested shifts from Bacteroides to Prevotella predominance following HIV-1 infection, which have not been found in animal models or in studies matched for HIV-1 transmission groups. In two independent cohorts of HIV-1-infected subjects and HIV-1-negative controls in Barcelona (n = 156) and Stockholm (n = 84), men who have sex with men (MSM) predominantly belonged to the Prevotella-rich enterotype whereas most non-MSM subjects were enriched in Bacteroides, independently of HIV-1 status, and with only a limited contribution of diet effects. Moreover, MSM had a significantly richer and more diverse fecal microbiota than non-MSM individuals. After stratifying for sexual orientation, there was no solid evidence of an HIV-specific dysbiosis. However, HIV-1 infection remained consistently associated with reduced bacterial richness, the lowest bacterial richness being observed in subjects with a virological-immune discordant response to antiretroviral therapy. Our findings indicate that HIV gut microbiome studies must control for HIV risk factors and suggest interventions on gut bacterial richness as possible novel avenues to improve HIV-1-associated immune dysfunction.
527.
Spatiotemporal variation of mammalian protein complex stoichiometries.
2016 Mar 14; 17(1): 47. Epub 2016 Mar 14; PubMed: 26975353.
Abstract + PDFRecent large-scale studies revealed cell-type specific proteomes. However, protein complexes, the basic functional modules of a cell, have been so far mostly considered as static entities with well-defined structures. The co-expression of their members has not been systematically charted at the protein level.
526.
Human gut microbes impact host serum metabolome and insulin sensitivity.
Pedersen HK, Gudmundsdottir V, Nielsen HB, Hyotylainen T, Nielsen T, Jensen BA, Forslund K, Hildebrand F, Prifti E, Falony G, Le Chatelier E, Levenez F, Doré J, Mattila I, Plichta DR, Pöhö P, Hellgren LI, Arumugam M, Sunagawa S, Vieira-Silva S, Jørgensen T, Holm JB, Trošt K, Consortium M, Kristiansen K, Brix S, Raes J, Wang J, Hansen T, Bork P, Brunak S, Oresic M, Ehrlich SD, Pedersen O
Abstract + PDFInsulin resistance is a forerunner state of ischaemic cardiovascular disease and type 2 diabetes. Here we show how the human gut microbiome impacts the serum metabolome and associates with insulin resistance in 277 non-diabetic Danish individuals. The serum metabolome of insulin-resistant individuals is characterized by increased levels of branched-chain amino acids (BCAAs), which correlate with a gut microbiome that has an enriched biosynthetic potential for BCAAs and is deprived of genes encoding bacterial inward transporters for these amino acids. Prevotella copri and Bacteroides vulgatus are identified as the main species driving the association between biosynthesis of BCAAs and insulin resistance, and in mice we demonstrate that P. copri can induce insulin resistance, aggravate glucose intolerance and augment circulating levels of BCAAs. Our findings suggest that microbial targets may have the potential to diminish insulin resistance and reduce the incidence of common metabolic and cardiovascular disorders.
525.
Transcriptional interactions suggest niche segregation among microorganisms in the human gut.
Plichta DR, Juncker AS, Bertalan M, Rettedal E, Gautier L, Varela E, Manichanh C, Fouqueray C, Levenez F, Nielsen T, Doré J, Machado AM, de Evgrafov MC, Hansen T, Jørgensen T, Bork P, Guarner F, Pedersen O, MetaHit-Consortium , Sommer MO, Ehrlich SD, Sicheritz-Pontén T, Brunak S, Nielsen HB
2016 Aug 26; 1(11): 16152. PubMed: 27564131.
Abstract + PDFThe human gastrointestinal (GI) tract is the habitat for hundreds of microbial species, of which many cannot be cultivated readily, presumably because of the dependencies between species(1). Studies of microbial co-occurrence in the gut have indicated community substructures that may reflect functional and metabolic interactions between cohabiting species(2,3). To move beyond species co-occurrence networks, we systematically identified transcriptional interactions between pairs of coexisting gut microbes using metagenomics and microarray-based metatranscriptomics data from 233 stool samples from Europeans. In 102 significantly interacting species pairs, the transcriptional changes led to a reduced expression of orthologous functions between the coexisting species. Specific species-species transcriptional interactions were enriched for functions important for H2 and CO2 homeostasis, butyrate biosynthesis, ATP-binding cassette (ABC) transporters, flagella assembly and bacterial chemotaxis, as well as for the metabolism of carbohydrates, amino acids and cofactors. The analysis gives the first insight into the microbial community-wide transcriptional interactions, and suggests that the regulation of gene expression plays an important role in species adaptation to coexistence and that niche segregation takes place at the transcriptional level.
524.
Ecogenomics and potential biogeochemical impacts of globally abundant ocean viruses.
Roux S, Brum JR, Dutilh BE, Sunagawa S, Duhaime MB, Loy A, Poulos BT, Solonenko N, Lara E, Poulain J, Pesant S, Kandels-Lewis S, Dimier C, Picheral M, Searson S, Cruaud C, Alberti A, Duarte CM, Gasol JM, Vaqué D, Tara-Oceans-Coordinators , Bork P, Acinas SG, Wincker P, Sullivan MB
Abstract + PDFOcean microbes drive biogeochemical cycling on a global scale. However, this cycling is constrained by viruses that affect community composition, metabolic activity, and evolutionary trajectories. Owing to challenges with the sampling and cultivation of viruses, genome-level viral diversity remains poorly described and grossly understudied, with less than 1% of observed surface-ocean viruses known. Here we assemble complete genomes and large genomic fragments from both surface- and deep-ocean viruses sampled during the Tara Oceans and Malaspina research expeditions, and analyse the resulting 'global ocean virome' dataset to present a global map of abundant, double-stranded DNA viruses complete with genomic and ecological contexts. A total of 15,222 epipelagic and mesopelagic viral populations were identified, comprising 867 viral clusters (defined as approximately genus-level groups). This roughly triples the number of known ocean viral populations and doubles the number of candidate bacterial and archaeal virus genera, providing a near-complete sampling of epipelagic communities at both the population and viral-cluster level. We found that 38 of the 867 viral clusters were locally or globally abundant, together accounting for nearly half of the viral populations in any global ocean virome sample. While two-thirds of these clusters represent newly described viruses lacking any cultivated representative, most could be computationally linked to dominant, ecologically relevant microbial hosts. Moreover, we identified 243 viral-encoded auxiliary metabolic genes, of which only 95 were previously known. Deeper analyses of four of these auxiliary metabolic genes (dsrC, soxYZ, P-II (also known as glnB) and amoC) revealed that abundant viruses may directly manipulate sulfur and nitrogen cycling throughout the epipelagic ocean. This viral catalog and functional analyses provide a necessary foundation for the meaningful integration of viruses into ecosystem models where they act as key players in nutrient cycling and trophic networks.
523.
A protocol for the systematic and quantitative measurement of protein-lipid interactions using the liposome-microarray-based assay.
Saliba AE, Vonkova I, Deghou S, Ceschia S, Tischer C, Kugler KG, Bork P, Ellenberg J, Gavin AC
2016 Jun; 11(6): 1021-38. Epub 2016 May 5; PubMed: 27149326.
Abstract + PDFLipids organize the activity of the cell's proteome through a complex network of interactions. The assembly of comprehensive atlases embracing all protein-lipid interactions is an important challenge that requires innovative methods. We recently developed a liposome-microarray-based assay (LiMA) that integrates liposomes, microfluidics and fluorescence microscopy and which is capable of measuring protein recruitment to membranes in a quantitative and high-throughput manner. Compared with previous assays that are labor-intensive and difficult to scale up, LiMA improves the protein-lipid interaction assay throughput by at least three orders of magnitude. Here we provide a step-by-step LiMA protocol that includes the following: (i) the serial and generic production of the liposome microarray; (ii) its integration into a microfluidic format; (iii) the measurement of fluorescently labeled protein (either purified proteins or from cell lysate) recruitment to liposomal membranes using high-throughput microscopy; (iv) automated image analysis pipelines to quantify protein-lipid interactions; and (v) data quality analysis. In addition, we discuss the experimental design, including the relevant quality controls. Overall, the protocol-including device preparation, assay and data analysis-takes 6-8 d. This protocol paves the way for protein-lipid interaction screens to be performed on the proteome and lipidome scales.
522.
The endosomal transcriptional regulator RNF11 integrates degradation and transport of EGFR.
Scharaw S, Iskar M, Ori A, Boncompain G, Laketa V, Poser I, Lundberg E, Perez F, Beck M, Bork P, Pepperkok R
2016 Nov 21; 215(4): 543-558. PubMed: 27872256.
Abstract + PDFStimulation of cells with epidermal growth factor (EGF) induces internalization and partial degradation of the EGF receptor (EGFR) by the endo-lysosomal pathway. For continuous cell functioning, EGFR plasma membrane levels are maintained by transporting newly synthesized EGFRs to the cell surface. The regulation of this process is largely unknown. In this study, we find that EGF stimulation specifically increases the transport efficiency of newly synthesized EGFRs from the endoplasmic reticulum to the plasma membrane. This coincides with an up-regulation of the inner coat protein complex II (COPII) components SEC23B, SEC24B, and SEC24D, which we show to be specifically required for EGFR transport. Up-regulation of these COPII components requires the transcriptional regulator RNF11, which localizes to early endosomes and appears additionally in the cell nucleus upon continuous EGF stimulation. Collectively, our work identifies a new regulatory mechanism that integrates the degradation and transport of EGFR in order to maintain its physiological levels at the plasma membrane.
521.
The Combination of X-Ray Crystallography and Cryo-Electron Microscopy Provides Insight into the Overall Architecture of the Dodecameric Rvb1/Rvb2 Complex.
Silva-Martin N, Daudén MI, Glatt S, Hoffmann NA, Kastritis P, Bork P, Beck M, Müller CW
Abstract + PDFThe Rvb1/Rvb2 complex is an essential component of many cellular pathways. The Rvb1/Rvb2 complex forms a dodecameric assembly where six copies of each subunit form two heterohexameric rings. However, due to conformational variability, the way the two rings pack together is still not fully understood. Here, we present the crystal structure and two cryo-electron microscopy reconstructions of the dodecameric, full-length Rvb1/Rvb2 complex, all showing that the interaction between the two heterohexameric rings is mediated through the Rvb1/Rvb2-specific domain II. Two conformations of the Rvb1/Rvb2 dodecamer are present in solution: a stretched conformation also present in the crystal, and a compact conformation. Novel asymmetric features observed in the reconstruction of the compact conformation provide additional insight into the plasticity of the Rvb1/Rvb2 complex.
520.
STITCH 5: augmenting protein-chemical interaction networks with tissue and affinity data.
2016 Jan 4; 44: D380-4. Epub 2015 Nov 20; PubMed: 26590256.
Abstract + PDFInteractions between proteins and small molecules are an integral part of biological processes in living organisms. Information on these interactions is dispersed over many databases, texts and prediction methods, which makes it difficult to get a comprehensive overview of the available evidence. To address this, we have developed STITCH ('Search Tool for Interacting Chemicals') that integrates these disparate data sources for 430 000 chemicals into a single, easy-to-use resource. In addition to the increased scope of the database, we have implemented a new network view that gives the user the ability to view binding affinities of chemicals in the interaction network. This enables the user to get a quick overview of the potential effects of the chemical on its interaction partners. For each organism, STITCH provides a global network; however, not all proteins have the same pattern of spatial expression. Therefore, only a certain subset of interactions can occur simultaneously. In the new, fifth release of STITCH, we have implemented functionality to filter out the proteins and chemicals not associated with a given tissue. The STITCH database can be downloaded in full, accessed programmatically via an extensive API, or searched via a redesigned web interface at http://stitch.embl.de.
519.
Colorectal Cancer and the Human Gut Microbiome: Reproducibility with Whole-Genome Shotgun Sequencing.
Abstract + PDFAccumulating evidence indicates that the gut microbiota affects colorectal cancer development, but previous studies have varied in population, technical methods, and associations with cancer. Understanding these variations is needed for comparisons and for potential pooling across studies. Therefore, we performed whole-genome shotgun sequencing on fecal samples from 52 pre-treatment colorectal cancer cases and 52 matched controls from Washington, DC. We compared findings from a previously published 16S rRNA study to the metagenomics-derived taxonomy within the same population. In addition, metagenome-predicted genes, modules, and pathways in the Washington, DC cases and controls were compared to cases and controls recruited in France whose specimens were processed using the same platform. Associations between the presence of fecal Fusobacteria, Fusobacterium, and Porphyromonas with colorectal cancer detected by 16S rRNA were reproduced by metagenomics, whereas higher relative abundance of Clostridia in cancer cases based on 16S rRNA was merely borderline based on metagenomics. This demonstrated that within the same sample set, most, but not all taxonomic associations were seen with both methods. Considering significant cancer associations with the relative abundance of genes, modules, and pathways in a recently published French metagenomics dataset, statistically significant associations in the Washington, DC population were detected for four out of 10 genes, three out of nine modules, and seven out of 17 pathways. In total, colorectal cancer status in the Washington, DC study was associated with 39% of the metagenome-predicted genes, modules, and pathways identified in the French study. More within and between population comparisons are needed to identify sources of variation and disease associations that can be reproduced despite these variations. Future studies should have larger sample sizes or pool data across studies to have sufficient power to detect associations that are reproducible and significant after correction for multiple testing.
518.
Global genetic capacity for mixotrophy in marine picocyanobacteria.
Yelton AP, Acinas SG, Sunagawa S, Bork P, Pedrós-Alió C, Chisholm SW
Abstract + PDFThe assimilation of organic nutrients by autotrophs, a form of mixotrophy, has been demonstrated in the globally abundant marine picocyanobacterial genera Prochlorococcus and Synechococcus. However, the range of compounds used and the distribution of organic compound uptake genes within picocyanobacteria are unknown. Here we analyze genomic and metagenomic data from around the world to determine the extent and distribution of mixotrophy in these phototrophs. Analysis of 49 Prochlorococcus and 18 Synechococcus isolate genomes reveals that all have the transporters necessary to take up amino acids, peptides and sugars. However, the number and type of transporters and associated catabolic genes differ between different phylogenetic groups, with low-light IV Prochlorococcus, and 5.1B, 5.2 and 5.3 Synechococcus strains having the largest number. Metagenomic data from 68 stations from the Tara Oceans expedition indicate that the genetic potential for mixotrophy in picocyanobacteria is globally distributed and differs between clades. Phylogenetic analyses indicate gradual organic nutrient transporter gene loss from the low-light IV to the high-light II Prochlorococcus. The phylogenetic differences in genetic capacity for mixotrophy, combined with the ubiquity of picocyanobacterial organic compound uptake genes suggests that mixotrophy has a more central role in picocyanobacterial ecology than was previously thought.The ISME Journal advance online publication, 3 May 2016; doi:10.1038/ismej.2016.64.
517.
The exploration of network motifs as potential drug targets from post-translational regulatory networks.
Zhang XD, Song J, Bork P, Zhao XM
Abstract + PDFPhosphorylation and proteolysis are among the most common post-translational modifications (PTMs), and play critical roles in various biological processes. More recent discoveries imply that the crosstalks between these two PTMs are involved in many diseases. In this work, we construct a post-translational regulatory network (PTRN) consists of phosphorylation and proteolysis processes, which enables us to investigate the regulatory interplays between these two PTMs. With the PTRN, we identify some functional network motifs that are significantly enriched with drug targets, some of which are further found to contain multiple proteins targeted by combinatorial drugs. These findings imply that the network motifs may be used to predict targets when designing new drugs. Inspired by this, we propose a novel computational approach called NetTar for predicting drug targets using the identified network motifs. Benchmarking results on real data indicate that our approach can be used for accurate prediction of novel proteins targeted by known drugs.
2015 30 publication(s).
516.
Mechismo: predicting the mechanistic impact of mutations and modifications on molecular interactions.
Betts MJ, Lu Q, Jiang Y, Drusko A, Wichmann O, Utz M, Valtierra-Gutiérrez IA, Schlesner M, Jaeger N, Jones DT, Pfister S, Lichter P, Eils R, Siebert R, Bork P, Apic G, Gavin AC, Russell RB
2015 Jan 30; 43(2): e10. Epub 2014 Nov 11; PubMed: 25392414.
Abstract + PDFSystematic interrogation of mutation or protein modification data is important to identify sites with functional consequences and to deduce global consequences from large data sets. Mechismo (mechismo.russellab.org) enables simultaneous consideration of thousands of 3D structures and biomolecular interactions to predict rapidly mechanistic consequences for mutations and modifications. As useful functional information often only comes from homologous proteins, we benchmarked the accuracy of predictions as a function of protein/structure sequence similarity, which permits the use of relatively weak sequence similarities with an appropriate confidence measure. For protein-protein, protein-nucleic acid and a subset of protein-chemical interactions, we also developed and benchmarked a measure of whether modifications are likely to enhance or diminish the interactions, which can assist the detection of modifications with specific effects. Analysis of high-throughput sequencing data shows that the approach can identify interesting differences between cancers, and application to proteomics data finds potential mechanistic insights for how post-translational modifications can alter biomolecular interactions.
515.
Quest for Orthologs (QfO) entails Quest for Tree of Life (QfToL): in Search of the Gene Stream.
Boeckmann B, Marcet-Houben M, Rees JA, Forslund K, Huerta-Cepas J, Muffato M, Yilmaz P, Xenarios I, Bork P, Lewis SE, Gabaldón T, Quest for Orthologs Species tree working group
2015 Jul 1; 7(7): 1988-99. PubMed: 26133389.
Abstract + PDFQuest for Orthologs (QfO) is a community effort with the goal to improve and benchmark orthology predictions. As quality assessment assumes prior knowledge on species phylogenies, we investigated the congruency between existing species trees by comparing the relationships of 147 QfO reference organisms from six Tree of Life (ToL) / species tree projects: the NCBI taxonomy, Opentree of Life, the sequenced species/species Tree of Life (sToL), the 16S rRNA database, and trees published by Ciccarelli et al in 2006, and by Huerta-Cepas et al in 2014. Our study reveals that each species tree suggests a different phylogeny: 87 out of 146 (60%) possible splits of a dichotomous and rooted tree are congruent, while all other splits are incongruent in at least one of the species trees. Topological differences are observed not only at deep speciation events, but also within younger clades, such as Hominidae, Rodentia, Laurasiatheria, or rosids. The evolutionary relationships of 27 archaea and bacteria are highly inconsistent. By assessing 458,108 gene trees from 65 genomes we show that consistent species topologies are more often supported by gene phylogenies than contradicting ones. The largest concordant species tree includes 77 of the QfO reference organisms at the most. Results are summarized in the form of a consensus ToL (http://swisstree.vital-it.ch/species_tree) that can serve different benchmarking purposes.
514.
Tara Oceans studies plankton at planetary scale. Introduction.
Bork P, Bowler C, De Vargas C, Gorsky G, Karsenti E, Wincker P
Abstract + PDFThe ocean is the largest ecosystem on Earth, and yet we know very little about it. This is particularly true for the plankton that inhabit the ocean. Although these organisms are at least as important for the Earth system as the rainforests and form the base of marine food webs, most plankton are invisible to the naked eye and thus are largely uncharacterized. To study this invisible world, the multinational Tara Oceans consortium, with use of the 110-foot research schooner Tara, sampled microscopic plankton at 210 sites and depths up to 2000 m in all the major oceanic regions during expeditions from 2009 through 2013.
513.
Patterns and ecological drivers of ocean viral communities.
Brum JR, Ignacio-Espinoza JC, Roux S, Doulcier G, Acinas SG, Alberti A, Chaffron S, Cruaud C, De Vargas C, Gasol JM, Gorsky G, Gregory AC, Guidi L, Hingamp P, Iudicone D, Not F, Ogata H, Pesant S, Poulos BT, Schwenck SM, Speich S, Dimier C, Kandels-Lewis S, Picheral M, Searson S, Bork P, Bowler C, Sunagawa S, Wincker P, Karsenti E, Sullivan MB
Abstract + PDFViruses influence ecosystems by modulating microbial population size, diversity, metabolic outputs, and gene flow. Here, we use quantitative double-stranded DNA (dsDNA) viral-fraction metagenomes (viromes) and whole viral community morphological data sets from 43 Tara Oceans expedition samples to assess viral community patterns and structure in the upper ocean. Protein cluster cataloging defined pelagic upper-ocean viral community pan and core gene sets and suggested that this sequence space is well-sampled. Analyses of viral protein clusters, populations, and morphology revealed biogeographic patterns whereby viral communities were passively transported on oceanic currents and locally structured by environmental conditions that affect host community structure. Together, these investigations establish a global ocean dsDNA viromic data set with analyses supporting the seed-bank hypothesis to explain how oceanic viral communities maintain high local diversity.
512.
Eukaryotic plankton diversity in the sunlit ocean.
De Vargas C, Audic S, Henry N, Decelle J, Mahé F, Logares R, Lara E, Berney C, Le Bescot N, Probert I, Carmichael M, Poulain J, Romac S, Colin S, Aury JM, Bittner L, Chaffron S, Dunthorn M, Engelen S, Flegontova O, Guidi L, Horák A, Jaillon O, Lima-Mendez G, Lukeš J, Malviya S, Morard R, Mulot M, Scalco E, Siano R, Vincent F, Zingone A, Dimier C, Picheral M, Searson S, Kandels-Lewis S, Acinas SG, Bork P, Bowler C, Gorsky G, Grimsley N, Hingamp P, Iudicone D, Not F, Ogata H, Pesant S, Raes J, Sieracki ME, Speich S, Stemmann L, Sunagawa S, Weissenbach J, Wincker P, Karsenti E.
Abstract + PDFMarine plankton support global biological and geochemical processes. Surveys of their biodiversity have hitherto been geographically restricted and have not accounted for the full range of plankton size. We assessed eukaryotic diversity from 334 size-fractionated photic-zone plankton communities collected across tropical and temperate oceans during the circumglobal Tara Oceans expedition. We analyzed 18S ribosomal DNA sequences across the intermediate plankton-size spectrum from the smallest unicellular eukaryotes (protists, >0.8 micrometers) to small animals of a few millimeters. Eukaryotic ribosomal diversity saturated at ~150,000 operational taxonomic units, about one-third of which could not be assigned to known eukaryotic groups. Diversity emerged at all taxonomic levels, both within the groups comprising the ~11,200 cataloged morphospecies of eukaryotic plankton and among twice as many other deep-branching lineages of unappreciated importance in plankton ecology studies. Most eukaryotic plankton biodiversity belonged to heterotrophic protistan groups, particularly those known to be parasites or symbiotic hosts.
511.
Prokaryotic ancestry and gene fusion of a dual localized peroxiredoxin in malaria parasites.
2015 Jan 5; 2(1): 5-13. PubMed: 28357258.
Abstract + PDFHorizontal gene transfer has emerged as a crucial driving force for the evolution of eukaryotes. This also includes Plasmodium falciparum and related economically and clinically relevant apicomplexan parasites, whose rather small genomes have been shaped not only by natural selection in different host populations but also by horizontal gene transfer following endosymbiosis. However, there is rather little reliable data on horizontal gene transfer between animal hosts or bacteria and apicomplexan parasites. Here we show that apicomplexan homologues of peroxiredoxin 5 (Prx5) have a prokaryotic ancestry and therefore represent a special subclass of Prx5 isoforms in eukaryotes. Using two different immunobiochemical approaches, we found that the P. falciparum Prx5 homologue is dually localized to the parasite plastid and cytosol. This dual localization is reflected by a modular Plasmodium-specific gene architecture consisting of two exons. Despite the plastid localization, our phylogenetic analyses contradict an acquisition by secondary endosymbiosis and support a gene fusion event following a horizontal prokaryote-to-eukaryote gene transfer in early apicomplexans. The results provide unexpected insights into the evolution of apicomplexan parasites as well as the molecular evolution of peroxiredoxins, an important family of ubiquitous, usually highly concentrated thiol-dependent hydroperoxidases that exert functions as detoxifying enzymes, redox sensors and chaperones.
510.
Disentangling type 2 diabetes and metformin treatment signatures in the human gut microbiota.
Forslund K, Hildebrand F, Nielsen T, Falony G, Le Chatelier E, Sunagawa S, Prifti E, Vieira-Silva S, Gudmundsdottir V, Krogh Pedersen H, Arumugam M, Kristiansen K, Voigt AY, Vestergaard H, Hercog R, Costea PI, Kultima JR, Li J, Jørgensen T, Levenez F, Dore J, MetaHIT C, Nielsen HB, Brunak S, Raes J, Hansen T, Wang J, Ehrlich SD, Bork P, Pedersen O
Abstract + PDFIn recent years, several associations between common chronic human disorders and altered gut microbiome composition and function have been reported. In most of these reports, treatment regimens were not controlled for and conclusions could thus be confounded by the effects of various drugs on the microbiota, which may obscure microbial causes, protective factors or diagnostically relevant signals. Our study addresses disease and drug signatures in the human gut microbiome of type 2 diabetes mellitus (T2D). Two previous quantitative gut metagenomics studies of T2D patients that were unstratified for treatment yielded divergent conclusions regarding its associated gut microbial dysbiosis. Here we show, using 784 available human gut metagenomes, how antidiabetic medication confounds these results, and analyse in detail the effects of the most widely used antidiabetic drug metformin. We provide support for microbial mediation of the therapeutic effects of metformin through short-chain fatty acid production, as well as for potential microbiota-mediated mechanisms behind known intestinal adverse effects in the form of a relative increase in abundance of Escherichia species. Controlling for metformin treatment, we report a unified signature of gut microbiome shifts in T2D with a depletion of butyrate-producing taxa. These in turn cause functional microbiome shifts, in part alleviated by metformin-induced changes. Overall, the present study emphasizes the need to disentangle gut microbiota signatures of specific human diseases from those of medication.
509.
Discovery and validation of the antimetastatic activity of citalopram in colorectal cancer.
2015 Apr-Jun; 2(2): e975080. PubMed: 27308430.
Abstract + PDFInverse gene expression profiling was recently shown to help drug repositioning. We showed that this approach works best for cancer and predicted novel drug candidates that may reduce metastasis in colorectal cancer. Antimetastatic activity of our predicted candidate, citalopram, was validated in an orthotopic mouse model of metastatic colorectal cancer.
508.
SMART: recent updates, new developments and status in 2015.
2015 Jan 28; 43: D257-60. Epub 2014 Oct 9; PubMed: 25300481.
Abstract + PDFSMART (Simple Modular Architecture Research Tool) is a web resource (http://smart.embl.de/) providing simple identification and extensive annotation of protein domains and the exploration of protein domain architectures. In the current version, SMART contains manually curated models for more than 1200 protein domains, with ∼200 new models since our last update article. The underlying protein databases were synchronized with UniProt, Ensembl and STRING, bringing the total number of annotated domains and other protein features above 100 million. SMART's 'Genomic' mode, which annotates proteins from completely sequenced genomes was greatly expanded and now includes 2031 species, compared to 1133 in the previous release. SMART analysis results pages have been completely redesigned and include links to several new information sources. A new, vector-based display engine has been developed for protein schematics in SMART, which can also be exported as high-resolution bitmap images for easy inclusion into other documents. Taxonomic tree displays in SMART have been significantly improved, and can be easily navigated using the integrated search engine.
507.
Determinants of community structure in the global plankton interactome.
Lima-Mendez G, Faust K, Henry N, Decelle J, Colin S, Carcillo F, Chaffron S, Ignacio-Espinosa JC, Roux S, Vincent F, Bittner L, Darzi Y, Wang J, Audic S, Berline L, Bontempi G, Cabello AM, Coppola L, Cornejo-Castillo FM, d'Ovidio F, De Meester L, Ferrera I, Garet-Delmas MJ, Guidi L, Lara E, Pesant S, Royo-Llonch M, Salazar G, Sánchez P, Sebastian M, Souffreau C, Dimier C, Picheral M, Searson S, Kandels-Lewis S, Gorsky G, Not F, Ogata H, Speich S, Stemmann L, Weissenbach J, Wincker P, Acinas SG, Sunagawa S, Bork P, Sullivan MB, Karsenti E, Bowler C, De Vargas C, Raes J
Abstract + PDFSpecies interaction networks are shaped by abiotic and biotic factors. Here, as part of the Tara Oceans project, we studied the photic zone interactome using environmental factors and organismal abundance profiles and found that environmental factors are incomplete predictors of community structure. We found associations across plankton functional types and phylogenetic groups to be nonrandomly distributed on the network and driven by both local and global patterns. We identified interactions among grazers, primary producers, viruses, and (mainly parasitic) symbionts and validated network-generated hypotheses using microscopy to confirm symbiotic relationships. We have thus provided a resource to support further research on ocean food webs and integrating biological components into ocean models.
506.
Defining a minimal cell: essentiality of small ORFs and ncRNAs in a genome-reduced bacterium.
Lluch-Senar M, Delgado J, Chen WH, Lloréns-Rico V, O'Reilly FJ, Wodke JA, Unal EB, Yus E, Martínez S, Nichols RJ, Ferrar T, Vivancos A, Schmeisky A, Stülke J, van Noort V, Gavin AC, Bork P, Serrano L
2015 Jan 21; 11(1): 780. PubMed: 25609650.
Abstract + PDFIdentifying all essential genomic components is critical for the assembly of minimal artificial life. In the genome-reduced bacterium Mycoplasma pneumoniae, we found that small ORFs (smORFs; < 100 residues), accounting for 10% of all ORFs, are the most frequently essential genomic components (53%), followed by conventional ORFs (49%). Essentiality of smORFs may be explained by their function as members of protein and/or DNA/RNA complexes. In larger proteins, essentiality applied to individual domains and not entire proteins, a notion we could confirm by expression of truncated domains. The fraction of essential non-coding RNAs (ncRNAs) non-overlapping with essential genes is 5% higher than of non-transcribed regions (0.9%), pointing to the important functions of the former. We found that the minimal essential genome is comprised of 33% (269,410 bp) of the M. pneumoniae genome. Our data highlight an unexpected hidden layer of smORFs with essential functions, as well as non-coding regions, thus changing the focus when aiming to define the minimal essential genome.
505.
Histone deacetylase inhibitors cause the selective depletion of bromodomain containing proteins.
2015 May 9; 14(5): 1350-60. Epub 2015 Mar 9; PubMed: 25755299.
Abstract + PDFHistone deacetylases (HDACs) and acetyltransferases control the epigenetic regulation of gene expression through modification of histone marks. Histone deacetylase inhibitors (HDACi) are small molecules that interfere with histone tail modification thus altering chromatin structure and epigenetically controlled pathways. They promote apoptosis in proliferating cells and are promising anti-cancer drugs. While some HDACis have already been approved for therapy and others are in different phases of clinical trials, the exact mechanism of action of this drug class remains elusive. Previous studies have shown that HDACis cause massive changes in chromatin structure but only moderate changes in gene expression. To which extent these changes manifest at the protein level has never been investigated on a proteome-wide scale. Here, we have studied HDACi-treated cells by large-scale mass spectrometry based proteomics. We show that HDACi treatment affects primarily the nuclear proteome and induces a selective decrease of bromodomain containing proteins (BCPs), the main readers of acetylated histone marks. By combining time-resolved proteome and transcriptome profiling, we show that BCPs are affected at the protein level as early as 12 hours after HDACi treatment and that their abundance is regulated by a combination of transcriptional and post-transcriptional mechanisms. Using gene silencing, we demonstrate that the decreased abundance of BCPs is sufficient to mediate important transcriptional changes induced by HDACi. Our data reveals a new aspect of the mechanism of action of HDACi that is mediated by an interplay between histone acetylation and the abundance of BCPs. Data are available via ProteomeXchange with identifier PXD001660 and NCBI Gene Expression Omnibus with identifier GSE64689.
504.
PTMcode v2: a resource for functional associations of post-translational modifications within and between proteins.
2015 Jan 28; 43: D494-502. Epub 2014 Oct 31; PubMed: 25361965.
Abstract + PDFThe post-translational regulation of proteins is mainly driven by two molecular events, their modification by several types of moieties and their interaction with other proteins. These two processes are interdependent and together are responsible for the function of the protein in a particular cell state. Several databases focus on the prediction and compilation of protein-protein interactions (PPIs) and no less on the collection and analysis of protein post-translational modifications (PTMs), however, there are no resources that concentrate on describing the regulatory role of PTMs in PPIs. We developed several methods based on residue co-evolution and proximity to predict the functional associations of pairs of PTMs that we apply to modifications in the same protein and between two interacting proteins. In order to make data available for understudied organisms, PTMcode v2 (http://ptmcode.embl.de) includes a new strategy to propagate PTMs from validated modified sites through orthologous proteins. The second release of PTMcode covers 19 eukaryotic species from which we collected more than 300 000 experimentally verified PTMs (>1 300 000 propagated) of 69 types extracting the post-translational regulation of >100 000 proteins and >100 000 interactions. In total, we report 8 million associations of PTMs regulating single proteins and over 9.4 million interplays tuning PPIs.
503.
The InterPro protein families database: the classification resource after 15 years.
Mitchell A, Chang HY, Daugherty L, Fraser M, Hunter S, Lopez R, McAnulla C, McMenamin C, Nuka G, Pesseat S, Sangrador-Vegas A, Scheremetjew M, Rato C, Yong SY, Bateman A, Punta M, Attwood TK, Sigrist CJ, Redaschi N, Rivoire C, Xenarios I, Kahn D, Guyot D, Bork P, Letunic I, Gough J, Oates M, Haft D, Huang H, Natale DA, Wu CH, Orengo C, Sillitoe I, Mi H, Thomas PD, Finn RD
2015 Jan 28; 43: D213-21. Epub 2014 Nov 26; PubMed: 25428371.
Abstract + PDFThe InterPro database (http://www.ebi.ac.uk/interpro/) is a freely available resource that can be used to classify sequences into protein families and to predict the presence of important domains and sites. Central to the InterPro database are predictive models, known as signatures, from a range of different protein family databases that have different biological focuses and use different methodological approaches to classify protein families and domains. InterPro integrates these signatures, capitalizing on the respective strengths of the individual databases, to produce a powerful protein classification resource. Here, we report on the status of InterPro as it enters its 15th year of operation, and give an overview of new developments with the database and its associated Web interfaces and software. In particular, the new domain architecture search tool is described and the process of mapping of Gene Ontology terms to InterPro is outlined. We also discuss the challenges faced by the resource given the explosive growth in sequence data in recent years. InterPro (version 48.0) contains 36 766 member database signatures integrated into 26 238 InterPro entries, an increase of over 3993 entries (5081 signatures), since 2012.
502.
Integrated Transcriptome and Proteome Analyses Reveal Organ-Specific Proteome Deterioration in Old Rats.
Ori A, Toyama BH, Harris MS, Bock T, Iskar M, Bork P, Ingolia NT, Hetzer MW, Beck M
Abstract + PDFAging is associated with the decline of protein, cell, and organ function. Here, we use an integrated approach to characterize gene expression, bulk translation, and cell biology in the brains and livers of young and old rats. We identify 468 differences in protein abundance between young and old animals. The majority are a consequence of altered translation output, that is, the combined effect of changes in transcript abundance and translation efficiency. In addition, we identify 130 proteins whose overall abundance remains unchanged but whose sub-cellular localization, phosphorylation state, or splice-form varies. While some protein-level differences appear to be a generic property of the rats' chronological age, the majority are specific to one organ. These may be a consequence of the organ's physiology or the chronological age of the cells within the tissue. Taken together, our study provides an initial view of the proteome at the molecular, sub-cellular, and organ level in young and old rats.
501.
Open science resources for the discovery and analysis of Tara Oceans data
Pesant S, Not F, Picheral M, Kandels-Lewis S, Le Bescot N, Gorsky G, Iudicone D, Karsenti E, Speich S, Troublé R, Dimier C, Searson S, Acinas SG, Bork P, Boss E, Bowler C, De Vargas C, Follows M, Grimsley G, Hingamp P, Jaillon O, Karp-Boss L, Krzic U, Ogata H, Raes J, Reynaud EG, Sardet C, Sieracki M, Stemmann L, Sullivan MB, Sunagawa S, Velayoudon D, Weissenbach J, Wincker P
2015 May 26; 2: 1-16. PID: 680.
Abstract + PDFThe Tara Oceans expedition (2009–2013) sampled contrasting ecosystems of the world oceans, collecting environmental data and plankton, from viruses to metazoans, for later analysis using modern sequencing and state-of-the-art imaging technologies. It surveyed 210 ecosystems in 20 biogeographic provinces, collecting over 35,000 samples of seawater and plankton. The interpretation of such an extensive collection of samples in their ecological context requires means to explore, assess and access raw and validated data sets. To address this challenge, the Tara Oceans Consortium offers open science resources, including the use of open access archives for nucleotides (ENA) and for environmental, biogeochemical, taxonomic and morphological data (PANGAEA), and the development of on line discovery tools and collaborative annotation tools for sequences and images. Here, we present an overview of Tara Oceans Data, and we provide detailed registries (data sets) of all campaigns (from port-to-port), stations and sampling events.
500.
Open science resources for the discovery and analysis of Tara Oceans data.
Pesant S, Not F, Picheral M, Kandels-Lewis S, Le Bescot N, Gorsky G, Iudicone D, Karsenti E, Speich S, Troublé R, Dimier C, Searson S, Tara Oceans Consortium Coordinators , Acinas SG, Bork P, Boss E, Bowler C, De Vargas C, Follows M, Gorsky G, Grimsley N, Hingamp P, Iudicone D, Jaillon O, Kandels-Lewis S, Karp-Boss L, Karsenti E, Krzic U, Not F, Ogata H, Pesant S, Raes J, Reynaud EG, Sardet C, Sieracki M, Speich S, Stemmann L, Sullivan MB, Sunagawa S, Velayoudon D, Weissenbach J, Wincker P.
Abstract + PDFThe Tara Oceans expedition (2009-2013) sampled contrasting ecosystems of the world oceans, collecting environmental data and plankton, from viruses to metazoans, for later analysis using modern sequencing and state-of-the-art imaging technologies. It surveyed 210 ecosystems in 20 biogeographic provinces, collecting over 35,000 samples of seawater and plankton. The interpretation of such an extensive collection of samples in their ecological context requires means to explore, assess and access raw and validated data sets. To address this challenge, the Tara Oceans Consortium offers open science resources, including the use of open access archives for nucleotides (ENA) and for environmental, biogeochemical, taxonomic and morphological data (PANGAEA), and the development of on line discovery tools and collaborative annotation tools for sequences and images. Here, we present an overview of Tara Oceans Data, and we provide detailed registries (data sets) of all campaigns (from port-to-port), stations and sampling events.
499.
Operon structure and cotranslational subunit association direct protein assembly in bacteria.
Shieh YW, Minguez P, Bork P, Auburger JJ, Guilbride DL, Kramer G, Bukau B
Abstract + PDFAssembly of protein complexes is considered a post-translational process involving random collision of subunits. We show that within the Escherichia coli cytosol, bacterial luciferase subunits LuxA and LuxB assemble into complexes close to the site of subunit synthesis. Assembly efficiency decreases markedly if subunits are synthesized on separate mRNAs from genes integrated at distant chromosomal sites. Subunit assembly initiates cotranslationally on nascent LuxB in vivo. The ribosome-associated chaperone Trigger Factor delays the onset of cotranslational interactions until the LuxB dimer interface is fully exposed. Protein assembly thus is directly coupled to the translation process, and involves spatially confined, actively chaperoned cotranslational subunit interactions. Bacterial gene organization into operons therefore reflects a fundamental mechanism for spatiotemporal regulation vital to effective cotranslational protein complex assembly.
498.
Structure and function of the global ocean microbiome.
Sunagawa S, Coelho LP, Chaffron S, Kultima JR, Labadie K, Salazar G, Djahanschiri B, Zeller G, Mende DR, Alberti A, Cornejo-Castillo FM, Costea PI, Cruaud C, d'Ovidio F, Engelen S, Ferrera I, Gasol JM, Guidi L, Hildebrand F, Kokoszka F, Lepoivre C, Lima-Mendez G, Poulain J, Poulos BT, Royo-Llonch M, Sarmento H, Vieira-Silva S, Dimier C, Picheral M, Searson S, Kandels-Lewis S, Bowler C, De Vargas C, Gorsky G, Grimsley N, Hingamp P, Iudicone D, Jaillon O, Not F, Ogata H, Pesant S, Speich S, Stemmann L, Sullivan MB, Weissenbach J, Wincker P, Karsenti E, Raes J, Acinas SG, Bork P
Abstract + PDFMicrobes are dominant drivers of biogeochemical processes, yet drawing a global picture of functional diversity, microbial community structure, and their ecological determinants remains a grand challenge. We analyzed 7.2 terabases of metagenomic data from 243 Tara Oceans samples from 68 locations in epipelagic and mesopelagic waters across the globe to generate an ocean microbial reference gene catalog with >40 million nonredundant, mostly novel sequences from viruses, prokaryotes, and picoeukaryotes. Using 139 prokaryote-enriched samples, containing >35,000 species, we show vertical stratification with epipelagic community composition mostly driven by temperature rather than other environmental factors or geography. We identify ocean microbial core functionality and reveal that >73% of its abundance is shared with the human gut microbiome despite the physicochemical differences between these two ecosystems.
497.
Computational eco-systems biology in Tara Oceans: translating data into knowledge.
Sunagawa S, Karsenti E, Bowler C, Bork P
2015 May 21; 11(5): 809. PubMed: 25999085.
Abstract + PDFIn molecular systems biology, data are flooding us at an ever?increasing pace, from genomic to transcriptomic and proteomic information, complemented by spatially and time?resolved data obtained at multiple scales. Computational biology usually integrates these layers of information at the cellular and biochemical levels. But how does the interplay between experimental and computational biology work if this information is coming not only from a cellular system, but from an entire ecosystem and if this ecosystem spans the entire Earth? Here, we illustrate some of the computational challenges and promises of large?scale eco?systems biology studies (Raes & Bork, 2008) in the context of the Tara Oceans project (Fig 1), which has arguably been one of the wettest wet laboratory experiments ever.
496.
STRING v10: protein-protein interaction networks, integrated over the tree of life.
Szklarczyk D, Franceschini A, Wyder S, Forslund K, Heller D, Huerta-Cepas J, Simonovic M, Roth A, Santos A, Tsafou KP, Kuhn M, Bork P, Jensen LJ, von Mering C
2015 Jan 28; 43: D447-52. Epub 2014 Oct 28; PubMed: 25352553.
Abstract + PDFThe many functional partnerships and interactions that occur between proteins are at the core of cellular processing and their systematic characterization helps to provide context in molecular systems biology. However, known and predicted interactions are scattered over multiple resources, and the available data exhibit notable differences in terms of quality and completeness. The STRING database (http://string-db.org) aims to provide a critical assessment and integration of protein-protein interactions, including direct (physical) as well as indirect (functional) associations. The new version 10.0 of STRING covers more than 2000 organisms, which has necessitated novel, scalable algorithms for transferring interaction information between organisms. For this purpose, we have introduced hierarchical and self-consistent orthology annotations for all interacting proteins, grouping the proteins into families at various levels of phylogenetic resolution. Further improvements in version 10.0 include a completely redesigned prediction pipeline for inferring protein-protein associations from co-expression data, an API interface for the R computing environment and improved statistical analysis for enrichment tests in user-provided networks.
495.
Shotgun metagenomes and multiple primer pairbarcode
combinations of amplicons reveal biases
in metabarcoding analyses of fungi
Tedersoo L, Anslan S, Bahram M, Põlme S, Riit T, Liiv I, Kõljalg U, Kisand V, Nilsson RH, Hildebrand F, Bork P, Abarenkov K
2015 May 13; 10: 1-43. PID: 679.
Abstract + PDFRapid development of high-throughput (HTS) molecular identification methods has revolutionized our knowledge about taxonomic diversity and ecology of fungi. However, PCR-based methods exhibit multiple technical shortcomings that may bias our understanding of the fungal kingdom. This study was initiated to quantify potential biases in fungal community ecology by comparing the relative performance of amplicon-free shotgun metagenomics and amplicons of nine primer pairs over seven nuclear ribosomal DNA (rDNA) regions often used in metabarcoding analyses. The internal transcribed spacer (ITS) barcodes ITS1 and ITS2 provided greater taxonomic and functional resolution and richness of operational taxonomic units (OTUs) at the 97% similarity threshold compared to barcodes located within the ribosomal small subunit (SSU) and large subunit (LSU) genes. All barcode-primer pair combinations provided consistent results in ranking taxonomic richness and recovering the importance of floristic variables in driving fungal community composition in soils of Papua New Guinea. The choice of forward primer explained up to 2.0% of the variation in OTU-level analysis of the ITS1 and ITS2 barcode data sets. Across the whole data set, barcode-primer pair combination explained 37.6–38.1% of the variation, which surpassed any environmental signal. Overall, the metagenomics data set recovered a similar taxonomic overview, but resulted in much lower fungal rDNA sequencing depth, inability to infer OTUs, and high uncertainty in identification. We recommend the use of ITS2 or the whole ITS region for metabarcoding and we advocate careful choice of primer pairs in consideration of the relative proportion of fungal DNA and expected dominant groups.
494.
Environmental characteristics of Agulhas rings affect interocean plankton transport.
Villar E, Farrant GK, Follows M, Garczarek L, Speich S, Audic S, Bittner L, Blanke B, Brum JR, Brunet C, Casotti R, Chase A, Dolan JR, d'Ortenzio F, Gattuso JP, Grima N, Guidi L, Hill CN, Jahn O, Jamet JL, Le Goff H, Lepoivre C, Malviya S, Pelletier E, Romagnan JB, Roux S, Santini S, Scalco E, Schwenck SM, Tanaka A, Testor P, Vannier T, Vincent F, Zingone A, Dimier C, Picheral M, Searson S, Kandels-Lewis S, Acinas SG, Bork P, Boss E, De Vargas C, Gorsky G, Ogata H, Pesant S, Sullivan MB, Sunagawa S, Wincker P, Karsenti E, Bowler C, Not F, Hingamp P, Iudicone D
Abstract + PDFAgulhas rings provide the principal route for ocean waters to circulate from the Indo-Pacific to the Atlantic basin. Their influence on global ocean circulation is well known, but their role in plankton transport is largely unexplored. We show that, although the coarse taxonomic structure of plankton communities is continuous across the Agulhas choke point, South Atlantic plankton diversity is altered compared with Indian Ocean source populations. Modeling and in situ sampling of a young Agulhas ring indicate that strong vertical mixing drives complex nitrogen cycling, shaping community metabolism and biogeochemical signatures as the ring and associated plankton transit westward. The peculiar local environment inside Agulhas rings may provide a selective mechanism contributing to the limited dispersal of Indian Ocean plankton populations into the Atlantic.
493.
Temporal and technical variability of human gut metagenomes.
2015 Apr 8; 16(1): 73. Epub 2015 Apr 8; PubMed: 25888008.
Abstract + PDFMetagenomics has become a prominent approach for exploring the role of the gut microbiota in human health. However, the temporal variability of the healthy gut microbiome has not yet been studied in depth using metagenomics and little is known about the effects of different sampling and preservation approaches. We performed metagenomic analysis on fecal samples from seven subjects collected over a period of up to two years to investigate temporal variability and assess preservation-induced variation, specifically, fresh frozen compared to RNALater. We also monitored short-term disturbances caused by antibiotic treatment and bowel cleansing in one subject.
492.
In situ structural analysis of the human nuclear pore complex.
von Appen A, Kosinski J, Sparks L, Ori A, DiGuilio AL, Vollmer B, Mackmull MT, Banterle N, Parca L, Kastritis P, Buczak K, Mosalaganti S, Hagen W, Andres-Pons A, Lemke EA, Bork P, Antonin W, Glavy JS, Bui KH, Beck M
Abstract + PDFNuclear pore complexes are fundamental components of all eukaryotic cells that mediate nucleocytoplasmic exchange. Determining their 110-megadalton structure imposes a formidable challenge and requires in situ structural biology approaches. Of approximately 30 nucleoporins (Nups), 15 are structured and form the Y and inner-ring complexes. These two major scaffolding modules assemble in multiple copies into an eight-fold rotationally symmetric structure that fuses the inner and outer nuclear membranes to form a central channel of ~60 nm in diameter. The scaffold is decorated with transport-channel Nups that often contain phenylalanine-repeat sequences and mediate the interaction with cargo complexes. Although the architectural arrangement of parts of the Y complex has been elucidated, it is unclear how exactly it oligomerizes in situ. Here we combine cryo-electron tomography with mass spectrometry, biochemical analysis, perturbation experiments and structural modelling to generate, to our knowledge, the most comprehensive architectural model of the human nuclear pore complex to date. Our data suggest previously unknown protein interfaces across Y complexes and to inner-ring complex members. We show that the transport-channel Nup358 (also known as Ranbp2) has a previously unanticipated role in Y-complex oligomerization. Our findings blur the established boundaries between scaffold and transport-channel Nups. We conclude that, similar to coated vesicles, several copies of the same structural building block-although compositionally identical-engage in different local sets of interactions and conformations.
491.
Lipid Cooperativity as a General Membrane-Recruitment Principle for PH Domains.
Vonkova I, Saliba AE, Deghou S, Anand K, Ceschia S, Doerks T, Galih A, Kugler KG, Maeda K, Rybin V, van Noort V, Ellenberg J, Bork P, Gavin AC
Abstract + PDFMany cellular processes involve the recruitment of proteins to specific membranes, which are decorated with distinctive lipids that act as docking sites. The phosphoinositides form signaling hubs, and we examine mechanisms underlying recruitment. We applied a physiological, quantitative, liposome microarray-based assay to measure the membrane-binding properties of 91 pleckstrin homology (PH) domains, the most common phosphoinositide-binding target. 10,514 experiments quantified the role of phosphoinositides in membrane recruitment. For most domains examined, the observed binding specificity implied cooperativity with additional signaling lipids. Analyses of PH domains with similar lipid-binding profiles identified a conserved motif, mutations in which-including some found in human cancers-induced discrete changes in binding affinities in vitro and protein mislocalization in vivo. The data set reveals cooperativity as a key mechanism for membrane recruitment and, by enabling the interpretation of disease-associated mutations, suggests avenues for the design of small molecules targeting PH domains.
490.
Detection of coding microsatellite frameshift mutations in DNA mismatch repair-deficient mouse intestinal tumors.
Woerner SM, Tosti E, Yuan YP, Kloor M, Bork P, Edelmann W, Gebert J
2015 Nov 11; 54(11): 1376-86. Epub 2014 Sep 11; PubMed: 25213383.
Abstract + PDFDifferent DNA mismatch repair (MMR)-deficient mouse strains have been developed as models for the inherited cancer predisposing Lynch syndrome. It is completely unresolved, whether coding mononucleotide repeat (cMNR) gene mutations in these mice can contribute to intestinal tumorigenesis and whether MMR-deficient mice are a suitable molecular model of human microsatellite instability (MSI)-associated intestinal tumorigenesis. A proof-of-principle study was performed to identify mouse cMNR-harboring genes affected by insertion/deletion mutations in MSI murine intestinal tumors. Bioinformatic algorithms were developed to establish a database of mouse cMNR-harboring genes. A panel of five mouse noncoding mononucleotide markers was used for MSI classification of intestinal matched normal/tumor tissues from MMR-deficient (Mlh1(-/-) , Msh2(-/-) , Msh2(LoxP/LoxP) ) mice. cMNR frameshift mutations of candidate genes were determined by DNA fragment analysis. Murine MSI intestinal tumors but not normal tissues from MMR-deficient mice showed cMNR frameshift mutations in six candidate genes (Elavl3, Tmem107, Glis2, Sdccag1, Senp6, Rfc3). cMNRs of mouse Rfc3 and Elavl3 are conserved in type and length in their human orthologs that are known to be mutated in human MSI colorectal, endometrial and gastric cancer. We provide evidence for the utility of a mononucleotide marker panel for detection of MSI in murine tumors, the existence of cMNR instability in MSI murine tumors, the utility of mouse subspecies DNA for identification of polymorphic repeats, and repeat conservation among some orthologous human/mouse genes, two of them showing instability in human and mouse MSI intestinal tumors. MMR-deficient mice hence are a useful molecular model system for analyzing MSI intestinal carcinogenesis. © 2014 Wiley Periodicals, Inc.
489.
Metabolic dependencies drive species co-occurrence in diverse microbial communities.
Zelezniak A, Andrejev S, Ponomarova O, Mende DR, Bork P, Patil KR
2015 May 19; 112(20): 6449-54. Epub 2015 May 4; PubMed: 25941371.
Abstract + PDFMicrobial communities populate most environments on earth and play a critical role in ecology and human health. Their composition is thought to be largely shaped by interspecies competition for the available resources, but cooperative interactions, such as metabolite exchanges, have also been implicated in community assembly. The prevalence of metabolic interactions in microbial communities, however, has remained largely unknown. Here, we systematically survey, by using a genome-scale metabolic modeling approach, the extent of resource competition and metabolic exchanges in over 800 communities. We find that, despite marked resource competition at the level of whole assemblies, microbial communities harbor metabolically interdependent groups that recur across diverse habitats. By enumerating flux-balanced metabolic exchanges in these co-occurring subcommunities we also predict the likely exchanged metabolites, such as amino acids and sugars, that can promote group survival under nutritionally challenging conditions. Our results highlight metabolic dependencies as a major driver of species co-occurrence and hint at cooperative groups as recurring modules of microbial community architecture.
488.
Dietary Modulation of Gut Microbiota Contributes to Alleviation of Both Genetic and Simple Obesity in Children.
Zhang C, Yin A, Li H, Wang R, Wu G, Shen J, Zhang M, Wang L, Hou Y, Ouyang H, Zhang Y, Zheng Y, Wang J, Lv X, Wang Y, Zhang F, Zeng B, Li W, Yan F, Zhao Y, Pang X, Zhang X, Fu H, Chen F, Zhao N, Hamaker BR, Bridgewater LC, Weinkove D, Clement K, Dore J, Holmes E, Xiao H, Zhao G, Yang S, Bork P, Nicholson JK, Wei H, Tang H, Zhang X, Zhao L
2015 Aug; 2(8): 968-84. PubMed: 26425705.
Abstract + PDFGut microbiota has been implicated as a pivotal contributing factor in diet-related obesity; however, its role in development of disease phenotypes in human genetic obesity such as Prader-Willi syndrome (PWS) remains elusive. In this hospitalized intervention trial with PWS (n = 17) and simple obesity (n = 21) children, a diet rich in non-digestible carbohydrates induced significant weight loss and concomitant structural changes of the gut microbiota together with reduction of serum antigen load and alleviation of inflammation. Co-abundance network analysis of 161 prevalent bacterial draft genomes assembled directly from metagenomic datasets showed relative increase of functional genome groups for acetate production from carbohydrates fermentation. NMR-based metabolomic profiling of urine showed diet-induced overall changes of host metabotypes and identified significantly reduced trimethylamine N-oxide and indoxyl sulfate, host-bacteria co-metabolites known to induce metabolic deteriorations. Specific bacterial genomes that were correlated with urine levels of these detrimental co-metabolites were found to encode enzyme genes for production of their precursors by fermentation of choline or tryptophan in the gut. When transplanted into germ-free mice, the pre-intervention gut microbiota induced higher inflammation and larger adipocytes compared with the post-intervention microbiota from the same volunteer. Our multi-omics-based systems analysis indicates a significant etiological contribution of dysbiotic gut microbiota to both genetic and simple obesity in children, implicating a potentially effective target for alleviation.
487.
Inter-individual differences in the gene content of human gut bacterial species.
2015 Apr 21; 16(1): 82. Epub 2015 Apr 21; PubMed: 25896518.
Abstract + PDFGene content differences in human gut microbes can lead to inter-individual phenotypic variations such as digestive capacity. It is unclear whether gene content variation is caused by differences in microbial species composition or by the presence of different strains of the same species; the extent of gene content variation in the latter is unknown. Unlike pan-genome studies of cultivable strains, the use of metagenomic data can provide an unbiased view of structural variation of gut bacterial strains by measuring them in their natural habitats, the gut of each individual in this case, representing native boundaries between gut bacterial populations. We analyzed publicly available metagenomics data from fecal samples to characterize inter-individual variation in gut bacterial species.
2014 20 publication(s).
486.
Addendum: Enterotypes of the human gut microbiome.
Arumugam M, Raes J, Pelletier E, Le Paslier D, Yamada T, Mende DR, Fernandes GR, Tap J, Bruls T, Batto JM, Bertalan M, Borruel N, Casellas F, Fernandez L, Gautier L, Hansen T, Hattori M, Hayashi T, Kleerebezem M, Kurokawa K, Leclerc M, Levenez F, Manichanh C, Nielsen HB, Nielsen T, Pons N, Poulain J, Qin J, Sicheritz-Ponten T, Tims S, Torrents D, Ugarte E, Zoetendal EG, Wang J, Guarner F, Pedersen O, de Vos WM, Brunak S, Doré J, MetaHIT C, Weissenbach J, Ehrlich SD, Bork P
Abstract + PDFIt has been drawn to our attention that the methods described in the main text and the Supplementary Information of this Article have been considered by some researchers to be insufficient to enable them to identify enterotypes in their own data sets. Enterotypes were originally defined in this Article (page 177) as “densely populated areas in a multi-dimensional space of community composition? and should not be seen as discrete clusters, but as a way of stratifying samples to reduce complexity. Additionally, the Fig. 2 legend should not imply that between-class analysis is simply a method of visualizing principal component analysis (PCA); rather, it is a supervised rather than an unsupervised analysis of data because it incorporates the outcome of clustering of data. To simplify enterotype identification in the original and other data sets, we have developed a comprehensive tutorial at http://enterotype.embl.de—which is a website on enterotypes that will be updated as methods improve. We thank Ivica Letunic and Paul Costea from EMBL for setting up the tutorial.
485.
An integrated approach for genome annotation of the eukaryotic thermophile Chaetomium thermophilum.
Bock T, Chen WH, Ori A, Malik N, Silva-Martin N, Huerta-Cepas J, Powell S, Kastritis PL, Smyshlyaev G, Vonkova I, Kirkpatrick J, Doerks T, Nesme L, Baßler J, Kos M, Hurt E, Carlomagno T, Gavin AC, Barabas O, Müller CW, van Noort V, Beck M, Bork P
2014 Dec 16; 42(22): 13525-33. Epub 2014 Nov 14; PubMed: 25398899.
Abstract + PDFThe thermophilic fungus Chaetomium thermophilum holds great promise for structural biology. To increase the efficiency of its biochemical and structural characterization and to explore its thermophilic properties beyond those of individual proteins, we obtained transcriptomics and proteomics data, and integrated them with computational annotation methods and a multitude of biochemical experiments conducted by the structural biology community. We considerably improved the genome annotation of Chaetomium thermophilum and characterized the transcripts and expression of thousands of genes. We furthermore show that the composition and structure of the expressed proteome of Chaetomium thermophilum is similar to its mesophilic relatives. Data were deposited in a publicly available repository and provide a rich source to the structural biology community.
484.
Blick zurück in die Zukunft der Bioinformatik
Bork P
In: Laborjournal7-8 2014(7-8) pp.73-75. BID: 22.
Publisher:
Abstract + PDFVor 20 Jahren wurden Bioinformatiker belächelt oder als Datenpiraten verunglimpft. Heute kommt die Biologie nicht mehr ohne sie aus.
Die Bioinformatik ist teilweise nur noch ein Sammelbegriff unter dem sich verschiedenste Teildiziplinen gruppieren.
Eigentlich ist Bioinformatik heute viel spannender, vielfältiger - auch erfolgsträchtiger - als vor 20 Jahren und kann disziplinübergreifend eingesetzt werden.
483.
Comments on "Human Dominant Disease Genes Are Enriched in Paralogs Originating from Whole Genome Duplication"
2014 Jul; 10(7): e1003758. PubMed: 25077479.
PDF481.
Luminal signalling links cell communication to tissue architecture during organogenesis.
Durdu S, Iskar M, Revenu C, Schieber N, Kunze A, Bork P, Schwab Y, Gilmour D
Abstract + PDFMorphogenesis is the process whereby cell collectives are shaped into differentiated tissues and organs. The self-organizing nature of morphogenesis has been recently demonstrated by studies showing that stem cells in three-dimensional culture can generate complex organoids, such as mini-guts, optic-cups and even mini-brains. To achieve this, cell collectives must regulate the activity of secreted signalling molecules that control cell differentiation, presumably through the self-assembly of microenvironments or niches. However, mechanisms that allow changes in tissue architecture to feedback directly on the activity of extracellular signals have not been described. Here we investigate how the process of tissue assembly controls signalling activity during organogenesis in vivo, using the migrating zebrafish lateral line primordium. We show that fibroblast growth factor (FGF) activity within the tissue controls the frequency at which it deposits rosette-like mechanosensory organs. Live imaging reveals that FGF becomes specifically concentrated in microluminal structures that assemble at the centre of these organs and spatially constrain its signalling activity. Genetic inhibition of microlumen assembly and laser micropuncture experiments demonstrate that microlumina increase signalling responses in participating cells, thus allowing FGF to coordinate the migratory behaviour of cell groups at the tissue rear. As the formation of a central lumen is a self-organizing property of many cell types, such as epithelia and embryonic stem cells, luminal signalling provides a potentially general mechanism to locally restrict, coordinate and enhance cell communication within tissues.
480.
Metagenomic insights into the human gut resistome and the forces that shape it.
Abstract + PDFWe show how metagenomic analysis of the human gut antibiotic resistome, compared across large populations and against environmental or agricultural resistomes, suggests a strong anthropogenic cause behind increasing antibiotic resistance in bacteria. This area has been the subject of intense and polarized debate driven by economic and political concerns; therefore such recently available insights address an important need. We derive and compare antibiotic resistomes of human gut microbes from 832 individuals from ten different countries. We observe and describe significant differences between samples from these countries in the gut resistance potential, in line with expectations from antibiotic usage and exposure in medical and food production contexts. Our results imply roles for both of these sources in increased resistance among pathogens in recent history. In contrast, other available metadata such as age, body mass index, sex, or health status have little effect on the antibiotic resistance potential of human gut microbes. Also watch the Video Abstract.
479.
Structural analysis of protein-ligand interactions: the binding of endogenous compounds and of synthetic drugs.
Gallina AM, Bork P, Bordo D
2014 Feb; 27(2): 65-72. PubMed: 24436123.
Abstract + PDFThe large number of macromolecular structures deposited with the Protein Data Bank (PDB) describing complexes between proteins and either physiological compounds or synthetic drugs made it possible a systematic analysis of the interactions occurring between proteins and their ligands. In this work, the binding pockets of about 4000 PDB protein-ligand complexes were investigated and amino acid and interaction types were analyzed. The residues observed with lowest frequency in protein sequences, Trp, His, Met, Tyr, and Phe, turned out to be the most abundant in binding pockets. Significant differences between drug-like and physiological compounds were found. On average, physiological compounds establish with respect to drugs about twice as many hydrogen bonds with protein atoms, whereas drugs rely more on hydrophobic interactions to establish target selectivity. The large number of PDB structures describing homologous proteins in complex with the same ligand made it possible to analyze the conservation of binding pocket residues among homologous protein structures bound to the same ligand, showing that Gly, Glu, Arg, Asp, His, and Thr are more conserved than other amino acids. Also in the cases in which the same ligand is bound to unrelated proteins, the binding pockets showed significant conservation in the residue types. In this case, the probability of co-occurrence of the same amino acid type in the binding pockets could be up to thirteen times higher than that expected on a random basis. The trends identified in this study may provide an useful guideline in the process of drug design and lead optimization. Copyright © 2014 John Wiley & Sons, Ltd.
478.
LotuS: an efficient and user-friendly OTU processing pipeline.
2014 Sep 30; 2(1): 30. Epub 2014 Sep 30; PubMed: 27367037.
Abstract + PDF16S ribosomal DNA (rDNA) amplicon sequencing is frequently used to analyse the structure of bacterial communities from oceans to the human microbiota. However, computational power is still a major bottleneck in the analysis of continuously enlarging metagenomic data sets. Analysis is further complicated by the technical complexity of current bioinformatics tools.
477.
Correction: LotuS: an efficient and user-friendly OTU processing pipeline.
2014; 2: 37. PubMed: 25317332.
Abstract + PDFBackground:
16S ribosomal DNA (rDNA) amplicon sequencing is frequently used to analyse the structure of bacterial communities from oceans to the human microbiota. However, computational power is still a major bottleneck in the analysis of continuously enlarging metagenomic data sets. Analysis is further complicated by the technical complexity of current bioinformatics tools.
Results:
Here we present the less operational taxonomic units scripts (LotuS), a fast and user-friendly open-source tool to calculate denoised, chimera-checked, operationa
l taxonomic units (OTUs). These are the basis to generate taxonomic abundance tables and phylogenetic trees from multiplexed, next-generation sequencing data (454, illumina MiSeq and HiSeq). LotuS is outstanding in its execution speed, as it can process 16S rDNA data up to two orders of magnitude faster than other existing pipelines. This is partly due to an included stand-alone fast simultaneous demultiplexer and quality filter C++ program, simple demultiplexer (sdm), which comes packaged with LotuS. Additionally, we sequenced two MiSeq runs with the intent to validate future pipelines by sequencing 40 technical
replicates; these are made available in this work.
Conclusion:
We show that LotuS analyses microbial 16S data with comparable or even better results than existing pipelines, requiring a fraction of the execution time and providing state-of-the-art denoising and phylogenetic reconstruction. LotuS is available through the following URL: http://psbweb05.psb.ugent.be/lotus.
Keywords:
OTU, 16S rDNA gene, Pipeline, Metagenomics, Demultiplexing
[This corrects the article on p. 30 in vol. 2.].
476.
STITCH 4: integration of protein-chemical interactions with user data.
2014 Jan 1; 42(Database issue): D401-7. Epub 2013 Nov 28; PubMed: 24293645.
Abstract + PDFSTITCH is a database of protein-chemical interactions that integrates many sources of experimental and manually curated evidence with text-mining information and interaction predictions. Available at http://stitch.embl.de, the resulting interaction network includes 390 000 chemicals and 3.6 million proteins from 1133 organisms. Compared with the previous version, the number of high-confidence protein-chemical interactions in human has increased by 45%, to 367 000. In this version, we added features for users to upload their own data to STITCH in the form of internal identifiers, chemical structures or quantitative data. For example, a user can now upload a spreadsheet with screening hits to easily check which interactions are already known. To increase the coverage of STITCH, we expanded the text mining to include full-text articles and added a prediction method based on chemical structures. We further changed our scheme for transferring interactions between species to rely on orthology rather than protein similarity. This improves the performance within protein families, where scores are now transferred only to orthologous proteins, but not to paralogous proteins. STITCH can be accessed with a web-interface, an API and downloadable files.
475.
An integrated catalog of reference genes in the human gut microbiome.
Li J, Jia H, Cai X, Zhong H, Feng Q, Sunagawa S, Arumugam M, Kultima JR, Prifti E, Nielsen T, Juncker AS, Manichanh C, Chen B, Zhang W, Levenez F, Wang J, Xu X, Xiao L, Liang S, Zhang D, Zhang Z, Chen W, Zhao H, Al-Aama JY, Edris S, Yang H, Wang J, Hansen T, Nielsen HB, Brunak S, Kristiansen K, Guarner F, Pedersen O, Doré J, Ehrlich SD, MetaHIT C, Bork P, Wang J.
2014 Aug 6; 32(8): 834-41. Epub 2014 Jul 6; PubMed: 24997786.
Abstract + PDFMany analyses of the human gut microbiome depend on a catalog of reference genes. Existing catalogs for the human gut microbiome are based on samples from single cohorts or on reference genomes or protein sequences, which limits coverage of global microbiome diversity. Here we combined 249 newly sequenced samples of the Metagenomics of the Human Intestinal Tract (MetaHit) project with 1,018 previously sequenced samples to create a cohort from three continents that is at least threefold larger than cohorts used for previous gene catalogs. From this we established the integrated gene catalog (IGC) comprising 9,879,896 genes. The catalog includes close-to-complete sets of genes for most gut microbes, which are also of considerably higher quality than in previous catalogs. Analyses of a group of samples from Chinese and Danish individuals using the catalog revealed country-specific gut microbial signatures. This expanded catalog should facilitate quantitative characterization of metagenomic, metatranscriptomic and metaproteomic data from the gut microbiome to understand its variation across populations in human health and disease.
474.
Metagenomic 16S rDNA Illumina tags are a powerful alternative to amplicon sequencing to explore diversity and structure of microbial communities.
Logares R, Sunagawa S, Salazar G, Cornejo-Castillo FM, Ferrera I, Sarmento H, Hingamp P, Ogata H, De Vargas C, Lima-Mendez G, Raes J, Poulain J, Jaillon O, Wincker P, Kandels-Lewis S, Karsenti E, Bork P, Acinas SG
2014 Sep 18; 16(9): 2659-71. Epub 2013 Sep 18; PubMed: 24102695.
Abstract + PDFSequencing of 16S rDNA polymerase chain reaction (PCR) amplicons is the most common approach for investigating environmental prokaryotic diversity, despite the known biases introduced during PCR. Here we show that 16S rDNA fragments derived from Illumina-sequenced environmental metagenomes (mi tags) are a powerful alternative to 16S rDNA amplicons for investigating the taxonomic diversity and structure of prokaryotic communities. As part of the Tara Oceans global expedition, marine plankton was sampled in three locations, resulting in 29 subsamples for which metagenomes were produced by shotgun Illumina sequencing (ca. 700 Gb). For comparative analyses, a subset of samples was also selected for Roche-454 sequencing using both shotgun (m454 tags; 13 metagenomes, ca. 2.4 Gb) and 16S rDNA amplicon (454 tags; ca. 0.075 Gb) approaches. Our results indicate that by overcoming PCR biases related to amplification and primer mismatch, mi tags may provide more realistic estimates of community richness and evenness than amplicon 454 tags. In addition, mi tags can capture expected beta diversity patterns. Using mi tags is now economically feasible given the dramatic reduction in high-throughput sequencing costs, having the advantage of retrieving simultaneously both taxonomic (Bacteria, Archaea and Eukarya) and functional information from the same microbial community.
473.
Identification and assembly of genomes and genetic elements in complex metagenomic samples without using reference genomes.
Nielsen HB, Almeida M, Juncker AS, Rasmussen S, Li J, Sunagawa S, Plichta DR, Gautier L, Pedersen AG, Le Chatelier E, Pelletier E, Bonde I, Nielsen T, Manichanh C, Arumugam M, Batto JM, Quintanilha Dos Santos MB, Blom N, Borruel N, Burgdorf KS, Boumezbeur F, Casellas F, Doré J, Dworzynski P, Guarner F, Hansen T, Hildebrand F, Kaas RS, Kennedy S, Kristiansen K, Kultima JR, Léonard P, Levenez F, Lund O, Moumen B, Le Paslier D, Pons N, Pedersen O, Prifti E, Qin J, Raes J, Sørensen S, Tap J, Tims S, Ussery DW, Yamada T, MetaHIT C, Renault P, Sicheritz-Ponten T, Bork P, Wang J, Brunak S, Ehrlich SD
2014 Aug 6; 32(8): 822-8. Epub 2014 Jul 6; PubMed: 24997787.
Abstract + PDFMost current approaches for analyzing metagenomic data rely on comparisons to reference genomes, but the microbial diversity of many environments extends far beyond what is covered by reference databases. De novo segregation of complex metagenomic data into specific biological entities, such as particular bacterial strains or viruses, remains a largely unsolved problem. Here we present a method, based on binning co-abundant genes across a series of metagenomic samples, that enables comprehensive discovery of new microbial organisms, viruses and co-inherited genetic entities and aids assembly of microbial genomes without the need for reference sequences. We demonstrate the method on data from 396 human gut microbiome samples and identify 7,381 co-abundance gene groups (CAGs), including 741 metagenomic species (MGS). We use these to assemble 238 high-quality microbial genomes and identify affiliations between MGS and hundreds of viruses or genetic entities. Our method provides the means for comprehensive profiling of the diversity within complex metagenomic samples.
472.
eggNOG v4.0: nested orthology inference across 3686 organisms.
Powell S, Forslund K, Szklarczyk D, Trachana K, Roth A, Huerta-Cepas J, Gabaldón T, Rattei T, Creevey CJ, Kuhn M, Jensen LJ, von Mering C, Bork P
2014 Jan 1; 42(Database issue): D231-9. Epub 2013 Dec 1; PubMed: 24297252.
Abstract + PDFWith the increasing availability of various 'omics data, high-quality orthology assignment is crucial for evolutionary and functional genomics studies. We here present the fourth version of the eggNOG database (available at http://eggnog.embl.de) that derives nonsupervised orthologous groups (NOGs) from complete genomes, and then applies a comprehensive characterization and analysis pipeline to the resulting gene families. Compared with the previous version, we have more than tripled the underlying species set to cover 3686 organisms, keeping track with genome project completions while prioritizing the inclusion of high-quality genomes to minimize error propagation from incomplete proteome sets. Major technological advances include (i) a robust and scalable procedure for the identification and inclusion of high-quality genomes, (ii) provision of orthologous groups for 107 different taxonomic levels compared with 41 in eggNOGv3, (iii) identification and annotation of particularly closely related orthologous groups, facilitating analysis of related gene families, (iv) improvements of the clustering and functional annotation approach, (v) adoption of a revised tree building procedure based on the multiple alignments generated during the process and (vi) implementation of quality control procedures throughout the entire pipeline. As in previous versions, eggNOGv4 provides multiple sequence alignments and maximum-likelihood trees, as well as broad functional annotation. Users can access the complete database of orthologous groups via a web interface, as well as through bulk download.
471.
A quantitative liposome microarray to systematically characterize protein-lipid interactions.
Saliba AE, Vonkova I, Ceschia S, Findlay GM, Maeda K, Tischer C, Deghou S, van Noort V, Bork P, Pawson T, Ellenberg J, Gavin AC
2014 Jan 24; 11(1): 47-50. Epub 2013 Nov 24; PubMed: 24270602.
Abstract + PDFLipids have a role in virtually all biological processes, acting as structural elements, scaffolds and signaling molecules, but they are still largely under-represented in known biological networks. Here we describe a liposome microarray-based assay (LiMA), a method that measures protein recruitment to membranes in a quantitative, automated, multiplexed and high-throughput manner.
470.
A Phylogeny-Based Benchmarking Test for Orthology Inference Reveals the Limitations of Function-Based Validation.
Abstract + PDFAccurate orthology prediction is crucial for many applications in the post-genomic era. The lack of broadly accepted benchmark tests precludes a comprehensive analysis of orthology inference. So far, functional annotation between orthologs serves as a performance proxy. However, this violates the fundamental principle of orthology as an evolutionary definition, while it is often not applicable due to limited experimental evidence for most species. Therefore, we constructed high quality "gold standard" orthologous groups that can serve as a benchmark set for orthology inference in bacterial species. Herein, we used this dataset to demonstrate 1) why a manually curated, phylogeny-based dataset is more appropriate for benchmarking orthology than other popular practices and 2) how it guides database design and parameterization through careful error quantification. More specifically, we illustrate how function-based tests often fail to identify false assignments, misjudging the true performance of orthology inference methods. We also examined how our dataset can instruct the selection of a "core" species repertoire to improve detection accuracy. We conclude that including more genomes at the proper evolutionary distances can influence the overall quality of orthology detection. The curated gene families, called Reference Orthologous Groups, are publicly available at http://eggnog.embl.de/orthobench2.
469.
Novel drug candidates for the treatment of metastatic colorectal cancer through global inverse gene expression profiling.
van Noort V, Schölch S, Iskar M, Zeller G, Ostertag K, Schweitzer C, Werner K, Weitz J, Koch M, Bork P
2014 Oct 15; 74(20): 5690-9. Epub 2014 Jul 18; PubMed: 25038229.
Abstract + PDFDrug-induced gene expression profiles that invert disease profiles have recently been illustrated to be a starting point for drug-repositioning. In this study, we validate this approach and focus on prediction of novel drugs for colorectal cancer (CRC), for which there is a pressing need to find novel anti-metastatic compounds. We computationally predicted three novel and still unknown compounds against CRC; citalopram (an anti-depressant), troglitazone (an anti-diabetic) and enilconazole (a fungicide). We verified the compounds by in vitro assays of clonogenic survival, proliferation and migration and in a subcutaneous mouse model. We found evidence that the mode-of-action of these compounds may be through inhibition of TGF-β signaling. Furthermore, one compound, citalopram, reduced tumor size as well as the number of circulating tumor cells and metastases in an orthotopic mouse model of CRC. This study proposes citalopram as a potential therapeutic option for CRC patients illustrating the potential of systems pharmacology.
468.
Classification and quantification of bacteriophage taxa in human gut metagenomes.
Abstract + PDFBacteriophages have key roles in microbial communities, to a large extent shaping the taxonomic and functional composition of the microbiome, but data on the connections between phage diversity and the composition of communities are scarce. Using taxon-specific marker genes, we identified and monitored 20 viral taxa in 252 human gut metagenomic samples, mostly at the level of genera. On average, five phage taxa were identified in each sample, with up to three of these being highly abundant. The abundances of most phage taxa vary by up to four orders of magnitude between the samples, and several taxa that are highly abundant in some samples are absent in others. Significant correlations exist between the abundances of some phage taxa and human host metadata: for example, 'Group 936 lactococcal phages' are more prevalent and abundant in Danish samples than in samples from Spain or the United States of America. Quantification of phages that exist as integrated prophages revealed that the abundance profiles of prophages are highly individual-specific and remain unique to an individual over a 1-year time period, and prediction of prophage lysis across the samples identified hundreds of prophages that are apparently active in the gut and vary across the samples, in terms of presence and lytic state. Finally, a prophage-host network of the human gut was established and includes numerous novel host-phage associations.
467.
Potential of fecal microbiota for early-stage detection of colorectal cancer.
Zeller G, Tap J, Voigt AY, Sunagawa S, Kultima JR, Costea PI, Amiot A, Böhm J, Brunetti F, Habermann N, Hercog R, Koch M, Luciani A, Mende DR, Schneider MA, Schrotz-King P, Tournigand C, Tran Van Nhieu J, Yamada T, Zimmermann J, Benes V, Kloor M, Ulrich CM, von Knebel Doeberitz M, Sobhani I, Bork P
2014 Nov 28; 10(11): 766. PubMed: 25432777.
Abstract + PDFSeveral bacterial species have been implicated in the development of colorectal carcinoma (CRC), but CRC-associated changes of fecal microbiota and their potential for cancer screening remain to be explored. Here, we used metagenomic sequencing of fecal samples to identify taxonomic markers that distinguished CRC patients from tumor-free controls in a study population of 156 participants. Accuracy of metagenomic CRC detection was similar to the standard fecal occult blood test (FOBT) and when both approaches were combined, sensitivity improved > 45% relative to the FOBT, while maintaining its specificity. Accuracy of metagenomic CRC detection did not differ significantly between early- and late-stage cancer and could be validated in independent patient and control populations (N = 335) from different countries. CRC-associated changes in the fecal microbiome at least partially reflected microbial community composition at the tumor itself, indicating that observed gene pool differences may reveal tumor-related host-microbe interactions. Indeed, we deduced a metabolic shift from fiber degradation in controls to utilization of host carbohydrates and amino acids in CRC patients, accompanied by an increase of lipopolysaccharide metabolism.
2013 19 publication(s).
466.
Evolution and functional cross-talk of protein post-translational modifications.
Beltrao P, Bork P, Krogan NJ, van Noort V
2013; 9(1): 714. PubMed: 24366814.
Abstract + PDFProtein post-translational modifications (PTMs) allow the cell to regulate protein activity and play a crucial role in the response to changes in external conditions or internal states. Advances in mass spectrometry now enable proteome wide characterization of PTMs and have revealed a broad functional role for a range of different types of modifications. Here we review advances in the study of the evolution and function of PTMs that were spurred by these technological improvements. We provide an overview of studies focusing on the origin and evolution of regulatory enzymes as well as the evolutionary dynamics of modification sites. Finally, we discuss different mechanisms of altering protein activity via post-translational regulation and progress made in the large-scale functional characterization of PTM function.
465.
The microbiome explored: recent insights and future challenges.
Blaser M, Bork P, Fraser C, Knight R, Wang J
2013 Mar 4; 11(3): 213-7. Epub 2013 Feb 4; PubMed: 23377500.
Abstract + PDFOne of the most exciting scientific advances in recent years has been the realization that commensal microorganisms are not simple 'passengers' in our bodies, but instead have key roles in our physiology, including our immune responses and metabolism, as well as in disease. These insights have been obtained, in part, through the work of large-scale, consortium-driven metagenomic projects. Here, five experts in the field of microbiome research discuss the most surprising and exciting new findings, and outline the future steps that will be necessary to elucidate the numerous roles of the microbiota in human health and disease and to develop viable therapeutic strategies.
464.
Human monogenic disease genes have frequently functionally redundant paralogs.
2013 May; 9(5): e1003073. PubMed: 23696728.
Abstract + PDFMendelian disorders are often caused by mutations in genes that are not lethal but induce functional distortions leading to diseases. Here we study the extent of gene duplicates that might compensate genes causing monogenic diseases. We provide evidence for pervasive functional redundancy of human monogenic disease genes (MDs) by duplicates by manifesting 1) genes involved in human genetic disorders are enriched in duplicates and 2) duplicated disease genes tend to have higher functional similarities with their closest paralogs in contrast to duplicated non-disease genes of similar age. We propose that functional compensation by duplication of genes masks the phenotypic effects of deleterious mutations and reduces the probability of purging the defective genes from the human population; this functional compensation could be further enhanced by higher purification selection between disease genes and their duplicates as well as their orthologous counterpart compared to non-disease genes. However, due to the intrinsic expression stochasticity among individuals, the deleterious mutations could still be present as genetic diseases in some subpopulations where the duplicate copies are expressed at low abundances. Consequently the defective genes are linked to genetic disorders while they continue propagating within the population. Our results provide insight into the molecular basis underlying the spreading of duplicated disease genes.
463.
Experimental characterization of the human non-sequence-specific nucleic acid interactome.
Duernberger G, Burckstummer T, Huber K, Giambruno R, Doerks T, Karayel E, Burkard TR, Kaupe I, Muller AC, Schonegger A, Ecker GF, Lohninger H, Bork P, Bennett KL, Superti-Furga G, Colinge J
2013 Jul 31; 14(7): R81. Epub 2013 Jul 31; PubMed: 23902751.
Abstract + PDFThe interactions between proteins and nucleic acids have a fundamental function in many biological processes, including gene transcription, RNA homeostasis, protein translation and pathogen sensing for innate immunity. While our knowledge of the ensemble of proteins that bind individual mRNAs in mammalian cells has been greatly augmented by recent surveys, no systematic study on the non-sequence-specific engagement of native human proteins with various types of nucleic acids has been reported.
462.
Country-specific antibiotic use practices impact the human gut resistome.
2013 Jul 29; 23(7): 1163-9. Epub 2013 Apr 8; PubMed: 23568836.
Abstract + PDFDespite increasing concerns over inappropriate use of antibiotics in medicine and food production, population-level resistance transfer into the human gut microbiota has not been demonstrated beyond individual case studies. To determine the "antibiotic resistance potential" for entire microbial communities, we employ metagenomic data and quantify the totality of known resistance genes in each community (its resistome) for 68 classes and subclasses of antibiotics. In 252 fecal metagenomes from three countries, we show that the most abundant resistance determinants are those for antibiotics also used in animals, and for antibiotics that have been available longer. Resistance genes are also more abundant in samples from Spain, Italy and France than from Denmark, the US, or Japan. Where comparable country-level data on antibiotic use in both humans and animals are available, differences in these statistics match the observed resistance potential differences. The results are robust over time as the antibiotic resistance determinants of individuals persist in the human gut flora for at least a year.
461.
STRING v9.1: protein-protein interaction networks, with increased coverage and integration.
Franceschini A, Szklarczyk D, Frankild S, Kuhn M, Simonovic M, Roth A, Lin J, Minguez P, Bork P, von Mering C, Jensen LJ
2013 Jan 1; 41: D808-15. Epub 2012 Nov 29; PubMed: 23203871.
Abstract + PDFComplete knowledge of all direct and indirect interactions between proteins in a given cell would represent an important milestone towards a comprehensive description of cellular mechanisms and functions. Although this goal is still elusive, considerable progress has been made-particularly for certain model organisms and functional systems. Currently, protein interactions and associations are annotated at various levels of detail in online resources, ranging from raw data repositories to highly formalized pathway databases. For many applications, a global view of all the available interaction data is desirable, including lower-quality data and/or computational predictions. The STRING database (http://string-db.org/) aims to provide such a global perspective for as many organisms as feasible. Known and predicted associations are scored and integrated, resulting in comprehensive protein networks covering >1100 organisms. Here, we describe the update to version 9.1 of STRING, introducing several improvements: (i) we extend the automated mining of scientific texts for interaction information, to now also include full-text articles; (ii) we entirely re-designed the algorithm for transferring interactions from one model organism to the other; and (iii) we provide users with statistical information on any functional enrichment observed in their networks.
460.
Exploring nucleo-cytoplasmic large DNA viruses in Tara Oceans microbial metagenomes.
Hingamp P, Grimsley N, Acinas SG, Clerissi C, Subirana L, Poulain J, Ferrera I, Sarmento H, Villar E, Lima-Mendez G, Faust K, Sunagawa S, Claverie JM, Moreau H, Desdevises Y, Bork P, Raes J, De Vargas C, Karsenti E, Kandels-Lewis S, Jaillon O, Not F, Pesant S, Wincker P, Ogata H
Abstract + PDFNucleo-cytoplasmic large DNA viruses (NCLDVs) constitute a group of eukaryotic viruses that can have crucial ecological roles in the sea by accelerating the turnover of their unicellular hosts or by causing diseases in animals. To better characterize the diversity, abundance and biogeography of marine NCLDVs, we analyzed 17 metagenomes derived from microbial samples (0.2-1.6 μm size range) collected during the Tara Oceans Expedition. The sample set includes ecosystems under-represented in previous studies, such as the Arabian Sea oxygen minimum zone (OMZ) and Indian Ocean lagoons. By combining computationally derived relative abundance and direct prokaryote cell counts, the abundance of NCLDVs was found to be in the order of 10(4)-10(5) genomes ml(-1) for the samples from the photic zone and 10(2)-10(3) genomes ml(-1) for the OMZ. The Megaviridae and Phycodnaviridae dominated the NCLDV populations in the metagenomes, although most of the reads classified in these families showed large divergence from known viral genomes. Our taxon co-occurrence analysis revealed a potential association between viruses of the Megaviridae family and eukaryotes related to oomycetes. In support of this predicted association, we identified six cases of lateral gene transfer between Megaviridae and oomycetes. Our results suggest that marine NCLDVs probably outnumber eukaryotic organisms in the photic layer (per given water mass) and that metagenomic sequence analyses promise to shed new light on the biodiversity of marine viruses and their interactions with potential hosts.The ISME Journal advance online publication, 11 April 2013; doi:10.1038/ismej.2013.59.
459.
Characterization of drug-induced transcriptional modules: towards drug repositioning and functional understanding.
Iskar M, Zeller G, Blattmann P, Campillos M, Kuhn M, Kaminska KH, Runz H, Gavin AC, Pepperkok R, van Noort V, Bork P
2013 Apr 30; 9: 662. PubMed: 23632384.
Abstract + PDFIn pharmacology, it is crucial to understand the complex biological responses that drugs elicit in the human organism and how well they can be inferred from model organisms. We therefore identified a large set of drug-induced transcriptional modules from genome-wide microarray data of drug-treated human cell lines and rat liver, and first characterized their conservation. Over 70% of these modules were common for multiple cell lines and 15% were conserved between the human in vitro and the rat in vivo system. We then illustrate the utility of conserved and cell-type-specific drug-induced modules by predicting and experimentally validating (i) gene functions, e.g., 10 novel regulators of cellular cholesterol homeostasis and (ii) new mechanisms of action for existing drugs, thereby providing a starting point for drug repositioning, e.g., novel cell cycle inhibitors and new modulators of α-adrenergic receptor, peroxisome proliferator-activated receptor and estrogen receptor. Taken together, the identified modules reveal the conservation of transcriptional responses towards drugs across cell types and organisms, and improve our understanding of both the molecular basis of drug action and human biology.
458.
Orthologous gene clusters and taxon signature genes for viruses of prokaryotes.
2013 Mar 7; 195(5): 941-50. Epub 2012 Dec 7; PubMed: 23222723.
Abstract + PDFViruses are the most abundant biological entities on earth and encompass a vast amount of genetic diversity. The recent rapid increase in the number of sequenced viral genomes has created unprecedented opportunities for gaining new insight into the structure and evolution of the virosphere. Here we present an update of the Phage Orthologous Groups (POGs), a collection of 4,542 clusters of orthologous genes from bacteriophages that now also includes viruses infecting archaea and encompasses more than 1,000 distinct virus genomes. Analysis of this expanded dataset shows that the number of POGs keeps growing without saturation and that a substantial majority of the POGs remain specific to viruses, lacking homologues in prokaryotic cells, outside of known proviruses. Thus, the great majority of virus genes apparently remains to be discovered. A complementary observation is that numerous viral genomes remain poorly if at all covered by POGs. The genome coverage by POGs is expected to increase as more genomes are sequenced. Taxon-specific, single-copy signature genes, that are not observed in prokaryotic genomes outside of detected proviruses, were identified for two-thirds of the 57 taxa (those with genomes available from at least 3 distinct viruses, with half of these present in all members of the respective taxon. These signatures can be used to specifically identify the presence and quantify the abundance of viruses from particular taxa in metagenomic samples and thus gain new insights into the ecology and evolution of viruses in relation to their hosts.
457.
Systematic identification of proteins that elicit drug side effects.
2013 Apr 30; 9: 663. PubMed: 23632385.
Abstract + PDFSide effect similarities of drugs have recently been employed to predict new drug targets, and networks of side effects and targets have been used to better understand the mechanism of action of drugs. Here, we report a large-scale analysis to systematically predict and characterize proteins that cause drug side effects. We integrated phenotypic data obtained during clinical trials with known drug-target relations to identify overrepresented protein-side effect combinations. Using independent data, we confirm that most of these overrepresentations point to proteins which, when perturbed, cause side effects. Of 1428 side effects studied, 732 were predicted to be predominantly caused by individual proteins, at least 137 of them backed by existing pharmacological or phenotypic data. We prove this concept in vivo by confirming our prediction that activation of the serotonin 7 receptor (HTR7) is responsible for hyperesthesia in mice, which, in turn, can be prevented by a drug that selectively inhibits HTR7. Taken together, we show that a large fraction of complex drug side effects are mediated by individual proteins and create a reference for such relations.
456.
Richness of human gut microbiome correlates with metabolic markers.
Le Chatelier E, Nielsen T, Qin J, Prifti E, Hildebrand F, Falony G, Almeida M, Arumugam M, Batto JM, Kennedy S, Leonard P, Li J, Burgdorf K, Grarup N, Jørgensen T, Brandslund I, Nielsen HB, Juncker AS, Bertalan M, Levenez F, Pons N, Rasmussen S, Sunagawa S, Tap J, Tims S, Zoetendal EG, Brunak S, Clément K, Doré J, Kleerebezem M, Kristiansen K, Renault P, Sicheritz-Ponten T, de Vos WM, Zucker JD, Raes J, Hansen T, MetaHIT Consortium , Bork P, Wang J, Ehrlich SD, Pedersen O
Abstract + PDFWe are facing a global metabolic health crisis provoked by an obesity epidemic. Here we report the human gut microbial composition in a population sample of 123 non-obese and 169 obese Danish individuals. We find two groups of individuals that differ by the number of gut microbial genes and thus gut bacterial richness. They contain known and previously unknown bacterial species at different proportions; individuals with a low bacterial richness (23% of the population) are characterized by more marked overall adiposity, insulin resistance and dyslipidaemia and a more pronounced inflammatory phenotype when compared with high bacterial richness individuals. The obese individuals among the lower bacterial richness group also gain more weight over time. Only a few bacterial species are sufficient to distinguish between individuals with high and low bacterial richness, and even between lean and obese participants. Our classifications based on variation in the gut microbiome identify subsets of individuals in the general white adult population who may be at increased risk of progressing to adiposity-associated co-morbidities.
455.
Accurate and universal delineation of prokaryotic species.
2013 Sep 28; 10(9): 881-4. Epub 2013 Jul 28; PubMed: 23892899.
Abstract + PDFThe exponentially increasing number of sequenced genomes necessitates fast, accurate, universally applicable and automated approaches for the delineation of prokaryotic species. We developed specI (species identification tool; http://www.bork.embl.de/software/specI/), a method to group organisms into species clusters based on 40 universal, single-copy phylogenetic marker genes. Applied to 3,496 prokaryotic genomes, specI identified 1,753 species clusters. Of 314 discrepancies with a widely used taxonomic classification, >62% were resolved by literature support.
454.
PTMcode: a database of known and predicted functional associations between post-translational modifications in proteins.
2013 Jan 1; 41: D306-11. Epub 2012 Nov 28; PubMed: 23193284.
Abstract + PDFPost-translational modifications (PTMs) are involved in the regulation and structural stabilization of eukaryotic proteins. The combination of individual PTM states is a key to modulate cellular functions as became evident in a few well-studied proteins. This combinatorial setting, dubbed the PTM code, has been proposed to be extended to whole proteomes in eukaryotes. Although we are still far from deciphering such a complex language, thousands of protein PTM sites are being mapped by high-throughput technologies, thus providing sufficient data for comparative analysis. PTMcode (http://ptmcode.embl.de) aims to compile known and predicted PTM associations to provide a framework that would enable hypothesis-driven experimental or computational analysis of various scales. In its first release, PTMcode provides PTM functional associations of 13 different PTM types within proteins in 8 eukaryotes. They are based on five evidence channels: a literature survey, residue co-evolution, structural proximity, PTMs at the same residue and location within PTM highly enriched protein regions (hotspots). PTMcode is presented as a protein-based searchable database with an interactive web interface providing the context of the co-regulation of nearly 75 000 residues in >10 000 proteins.
453.
Cell type-specific nuclear pores: a case in point for context-dependent stoichiometry of molecular machines.
Ori A, Banterle N, Iskar M, Andrés-Pons A, Escher C, Khanh Bui H, Sparks L, Solis-Mezarino V, Rinner O, Bork P, Lemke EA, Beck M
2013 Mar 19; 9: 648. PubMed: 23511206.
Abstract + PDFTo understand the structure and function of large molecular machines, accurate knowledge of their stoichiometry is essential. In this study, we developed an integrated targeted proteomics and super-resolution microscopy approach to determine the absolute stoichiometry of the human nuclear pore complex (NPC), possibly the largest eukaryotic protein complex. We show that the human NPC has a previously unanticipated stoichiometry that varies across cancer cell types, tissues and in disease. Using large-scale proteomics, we provide evidence that more than one third of the known, well-defined nuclear protein complexes display a similar cell type-specific variation of their subunit stoichiometry. Our data point to compositional rearrangement as a widespread mechanism for adapting the functions of molecular machines toward cell type-specific constraints and context-dependent needs, and highlight the need of deeper investigation of such structural variants.
452.
DvD: An R/Cytoscape pipeline for drug repurposing using public repositories of gene expression data.
Pacini C, Iorio F, Gonçalves E, Iskar M, Klabunde T, Bork P, Saez-Rodriguez J
2013 Jan 1; 29(1): 132-4. Epub 2012 Nov 4; PubMed: 23129297.
Abstract + PDFSUMMARY: Drug versus Disease (DvD) provides a pipeline, available through R or Cytoscape, for the comparison of drug and disease gene expression profiles from public microarray repositories. Negatively correlated profiles can be used to generate hypotheses of drug-repurposing whilst positively correlated profiles may be used to infer side-effects of drugs. DvD allows users to compare drug and disease signatures with dynamic access to databases Array Express, GEO and data from the Connectivity Map.Availability and Implementation: R package (submitted to Bioconductor) under GPL 3 and Cytoscape plug-in freely available for download at www.ebi.ac.uk/saezrodriguez/DVD/ CONTACT: saezrodriguez@ebi.ac.uk SUPPLEMENTARY INFORMATION: Accompanies this paper.
451.
Genomic variation landscape of the human gut microbiome.
Schloissnig S, Arumugam M, Sunagawa S, Mitreva M, Tap J, Zhu A, Waller AS, Mende DR, Kultima JR, Martin J, Kota K, Sunyaev SR, Weinstock GM, Bork P
Abstract + PDFWhereas large-scale efforts have rapidly advanced the understanding and practical impact of human genomic variation, the practical impact of variation is largely unexplored in the human microbiome. We therefore developed a framework for metagenomic variation analysis and applied it to 252 faecal metagenomes of 207 individuals from Europe and North America. Using 7.4 billion reads aligned to 101 reference species, we detected 10.3 million single nucleotide polymorphisms (SNPs), 107,991 short insertions/deletions, and 1,051 structural variants. The average ratio of non-synonymous to synonymous polymorphism rates of 0.11 was more variable between gut microbial species than across human hosts. Subjects sampled at varying time intervals exhibited individuality and temporal stability of SNP variation patterns, despite considerable composition changes of their gut microbiota. This indicates that individual-specific strains are not easily replaced and that an individual might have a unique metagenomic genotype, which may be exploitable for personalized diet or drug intake.
450.
Metagenomic species profiling using universal phylogenetic marker genes.
Sunagawa S, Mende DR, Zeller G, Izquierdo-Carrasco F, Berger SA, Kultima JR, Coelho LP, Arumugam M, Tap J, Nielsen HB, Rasmussen S, Brunak S, Pedersen O, Guarner F, de Vos WM, Wang J, Li J, Doré J, Ehrlich SD, Stamatakis A, Bork P
2013 Dec 20; 10(12): 1196-9. Epub 2013 Oct 20; PubMed: 24141494.
Abstract + PDFTo quantify known and unknown microorganisms at species-level resolution using shotgun sequencing data, we developed a method that establishes metagenomic operational taxonomic units (mOTUs) based on single-copy phylogenetic marker genes. Applied to 252 human fecal samples, the method revealed that on average 43% of the species abundance and 58% of the richness cannot be captured by current reference genome-based methods. An implementation of the method is available at http://www.bork.embl.de/software/mOTU/.
449.
Individuality and temporal stability of the human gut microbiome.
Sunagawa S, Schloissnig S, Arumugam M, Forslund K, Mitreva M, Tap J, Zhu A, Waller AS, Mende DR, Kultima JR, Martin J, Kota K, Sunyaev SR, Typas A, Weinstock GM, Bork P
2013; 2(Suppl): 120. PubMed: 29805877.
Abstract + PDFThe breakthrough of next generation sequencing-technologies has enabled large-scale studies of natural microbial communities and the 16S rRNA genes have been widely used as a phylogenetic marker to study community structure. However, major limitations of this approach are that neither strain-level resolution nor genomic context of microorganisms can be provided. This information, however, is crucial to answer fundamental questions about the temporal stability and distinctiveness of natural microbial communities.
448.
Consistent mutational paths predict eukaryotic thermostability.
van Noort V, Bradatsch B, Arumugam M, Amlacher S, Bange G, Creevey CJ, Falk S, Mende DR, Sinning I, Hurt E, Bork P
2013 Jan 10; 13(1): 7. Epub 2013 Jan 10; PubMed: 23305080.
Abstract + PDFABSTRACT: BACKGROUND: Proteomes of thermophilic prokaryotes have been instrumental in structural biology and successfully exploited in biotechnology, however many proteins required for eukaryotic cell function are absent from bacteria or archaea. With Chaetomium thermophilum, Thielavia terrestris and Thielavia heterothallica three genome sequences of thermophilic eukaryotes have been published. RESULTS: Studying the genomes and proteomes of these thermophilic fungi, we found common strategies of thermal adaptation across the different kingdoms of Life, including amino acid biases and a reduced genome size. A phylogenetics-guided comparison of thermophilic proteomes with those of other, mesophilic Sordariomycetes revealed consistent amino acid substitutions associated to thermophily that were also present in an independent lineage of thermophilic fungi. The most consistent pattern is the substitution of lysine by arginine, which we could find in almost all lineages but has not been extensively used in protein stability engineering. By exploiting mutational paths towards the thermophiles, we could predict particular amino acid residues in individual proteins that contribute to thermostability and validated some of them experimentally. By determining the three-dimensional structure of an exemplar protein from C. Thermophilum (Arx1), we could also characterise the molecular consequences of some of these mutations. CONCLUSIONS: The comparative analysis of these three genomes not only enhances our understanding of the evolution of thermophily, but also provides new ways to engineer protein stability.
2012 18 publication(s).
447.
Role for urea in nitrification by polar marine Archaea.
Alonso-Sáez L, Waller AS, Mende DR, Bakker K, Farnelid H, Yager PL, Lovejoy C, Tremblay JE, Potvin M, Heinrich F, Estrada M, Riemann L, Bork P, Pedrós-Alió C, Bertilsson S
2012 Oct 30; 109(44): 17989-94. Epub 2012 Oct 1; PubMed: 23027926.
Abstract + PDFDespite the high abundance of Archaea in the global ocean, their metabolism and biogeochemical roles remain largely unresolved. We investigated the population dynamics and metabolic activity of Thaumarchaeota in polar environments, where these microorganisms are particularly abundant and exhibit seasonal growth. Thaumarchaeota were more abundant in deep Arctic and Antarctic waters and grew throughout the winter at surface and deeper Arctic halocline waters. However, in situ single-cell activity measurements revealed a low activity of this group in the uptake of both leucine and bicarbonate (<5% Thaumarchaeota cells active), which is inconsistent with known heterotrophic and autotrophic thaumarchaeal lifestyles. These results suggested the existence of alternative sources of carbon and energy. Our analysis of an environmental metagenome from the Arctic winter revealed that Thaumarchaeota had pathways for ammonia oxidation and, unexpectedly, an abundance of genes involved in urea transport and degradation. Quantitative PCR analysis confirmed that most polar Thaumarchaeota had the potential to oxidize ammonia, and a large fraction of them had urease genes, enabling the use of urea to fuel nitrification. Thaumarchaeota from Arctic deep waters had a higher abundance of urease genes than those near the surface suggesting genetic differences between closely related archaeal populations. In situ measurements of urea uptake and concentration in Arctic waters showed that small-sized prokaryotes incorporated the carbon from urea, and the availability of urea was often higher than that of ammonium. Therefore, the degradation of urea may be a relevant pathway for Thaumarchaeota and other microorganisms exposed to the low-energy conditions of dark polar waters.
446.
OGEE: an online gene essentiality database.
2012 Jan 10; 40(Database issue): D901-6. Epub 2011 Nov 10; PubMed: 22075992.
Abstract + PDFOGEE is an Online GEne Essentiality database. Its main purpose is to enhance our understanding of the essentiality of genes. This is achieved by collecting not only experimentally tested essential and non-essential genes, but also associated gene features such as expression profiles, duplication status, conservation across species, evolutionary origins and involvement in embryonic development. We focus on large-scale experiments and complement our data with text-mining results. Genes are organized into data sets according to their sources. Genes with variable essentiality status across data sets are tagged as conditionally essential, highlighting the complex interplay between gene functions and environments. Linked tools allow the user to compare gene essentiality among different gene groups, or compare features of essential genes to non-essential genes, and visualize the results. OGEE is freely available at http://ogeedb.embl.de.
445.
Younger genes are less likely to be essential than older genes, and duplicates are less likely to be essential than singletons of the same age.
2012 Jul 7; 29(7): 1703-6. Epub 2012 Mar 7; PubMed: 22319151.
Abstract + PDFRecently duplicated genes are believed to often overlap in function and expression. A priori, they are thus less likely to be essential. While this was indeed observed in yeast, mouse singletons and duplicates were reported to be equally often essential. This contradiction can only partly be explained by experimental biases. We herein show that older genes (i.e., genes with earlier phyletic origin) are more likely to be essential, regardless of their duplication status. At a given phyletic gene age, duplicates are always less likely to be essential compared to singletons. The 'paradoxical' high essentiality among mouse gene duplicates is then caused by different age profiles of singletons and duplicates, with the latter tending to be derived from older genes.
444.
The Tenth Asia Pacific Bioinformatics Conference (APBC 2012).
Chen YP, Bork P
2012 Jan 17; 13 Suppl 1: I1. Epub 2012 Jan 17; PubMed: 22369290.
PDF443.
Annotation of the M. tuberculosis Hypothetical Orfeome: Adding Functional Information to More than Half of the Uncharacterized Proteins.
Abstract + PDFThe genome of Mycobacterium tuberculosis (H37Rv) contains 4,019 protein coding genes, of which more than thousand have been categorized as 'hypothetical' implying that for these not even weak functional associations could be identified so far. We here predict reliable functional indications for half of this large hypothetical orfeome: 497 genes can be annotated based on orthology, and another 125 can be linked to interacting proteins via integrated genomic context analysis and literature mining. The assignments include newly identified clusters of interacting proteins, hypothetical genes that are associated to well known pathways and putative disease-relevant targets. All together, we have raised the fraction of the proteome with at least some functional annotation to 88% which should considerably enhance the interpretation of large-scale experiments targeting this medically important organism.
442.
A 15q24 microdeletion in transient myeloproliferative disease (TMD) and acute megakaryoblastic leukaemia (AMKL) implicates PML and SUMO3 in the leukaemogenesis of TMD/AMKL.
Haemmerling S, Behnisch W, Doerks T, Korbel JO, Bork P, Moog U, Hentze S, Grasshoff U, Bonin M, Rieß O, Janssen JW, Jauch A, Bartram CR, Reinhardt D, Koch KA, Bandapalli OR, Kulozik AE
2012 Apr 1; 157(2): 180-7. Epub 2012 Feb 1; PubMed: 22296450.
Abstract + PDFTransient myeloproliferative disorder (TMD) of the newborn and acute megakaryoblastic leukaemia (AMKL) in children with Down syndrome (DS) represent paradigmatic models of leukaemogenesis. Chromosome 21 gene dosage effects and truncating mutations of the X-chromosomal transcription factor GATA1 synergize to trigger TMD and AMKL in most patients. Here, we report the occurrence of TMD, which spontaneously remitted and later progressed to AMKL in a patient without DS but with a distinct dysmorphic syndrome. Genetic analysis of the leukaemic clone revealed somatic trisomy 21 and a truncating GATA1 mutation. The analysis of the patient's normal blood cell DNA on a genomic single nucleotide polymorphism (SNP) array revealed a de novo germ line 2·58 Mb 15q24 microdeletion including 41 known genes encompassing the tumour suppressor PML. Genomic context analysis of proteins encoded by genes that are included in the microdeletion, chromosome 21-encoded proteins and GATA1 suggests that the microdeletion may trigger leukaemogenesis by disturbing the balance of a hypothetical regulatory network of normal megakaryopoiesis involving PML, SUMO3 and GATA1. The 15q24 microdeletion may thus represent the first genetic hit to initiate leukaemogenesis and implicates PML and SUMO3 as novel components of the leukaemogenic network in TMD/AMKL.
441.
InterPro in 2011: new developments in the family and domain prediction database.
Hunter S, Jones P, Mitchell A, Apweiler R, Attwood TK, Bateman A, Bernard T, Binns D, Bork P, Burge S, de Castro E, Coggill P, Corbett M, Das U, Daugherty L, Duquenne L, Finn RD, Fraser M, Gough J, Haft D, Hulo N, Kahn D, Kelly E, Letunic I, Lonsdale D, Lopez R, Madera M, Maslen J, McAnulla C, McDowall J, McMenamin C, Mi H, Mutowo-Muellenet P, Mulder N, Natale D, Orengo C, Pesseat S, Punta M, Quinn AF, Rivoire C, Sangrador-Vegas A, Selengut JD, Sigrist CJ, Scheremetjew M, Tate J, Thimmajanarthanan M, Thomas PD, Wu CH, Yeats C, Yong SY
2012 Jan 1; 40: D306-12. Epub 2011 Nov 16; PubMed: 22096229.
Abstract + PDFInterPro (http://www.ebi.ac.uk/interpro/) is a database that integrates diverse information about protein families, domains and functional sites, and makes it freely available to the public via Web-based interfaces and services. Central to the database are diagnostic models, known as signatures, against which protein sequences can be searched to determine their potential function. InterPro has utility in the large-scale analysis of whole genomes and meta-genomes, as well as in characterizing individual protein sequences. Herein we give an overview of new developments in the database and its associated software since 2009, including updates to database content, curation processes and Web and programmatic interfaces.
440.
Drug discovery in the age of systems biology: the rise of computational approaches for data integration.
2012 Aug 5; 23(4): 609-16. Epub 2011 Dec 5; PubMed: 22153034.
Abstract + PDFThe increased availability of large-scale open-access resources on bioactivities of small molecules has a significant impact on pharmacology facilitated mainly by computational approaches that digest the vast amounts of data. We discuss here how computational data integration enables systemic views on a drug's action and allows to tackle complex problems such as the large-scale prediction of drug targets, drug repurposing, the molecular mechanisms, cellular responses or side effects. We particularly focus on computational methods that leverage various cell-based transcriptional, proteomic and phenotypic profiles of drug response in order to gain a systemic view of drug action at the molecular, cellular and whole-organism scale.
439.
STITCH 3: zooming in on protein-chemical interactions.
2012 Jan 1; 40: D876-80. Epub 2011 Nov 9; PubMed: 22075997.
Abstract + PDFTo facilitate the study of interactions between proteins and chemicals, we have created STITCH, an aggregated database of interactions connecting over 300 000 chemicals and 2.6 million proteins from 1133 organisms. Compared to the previous version, the number of chemicals with interactions and the number of high-confidence interactions both increase 4-fold. The database can be accessed interactively through a web interface, displaying interactions in an integrated network view. It is also available for computational studies through downloadable files and an API. As an extension in the current version, we offer the option to switch between two levels of detail, namely whether stereoisomers of a given compound are shown as a merged entity or as separate entities. Separate display of stereoisomers is necessary, for example, for carbohydrates and chiral drugs. Combining the isomers increases the coverage, as interaction databases and publications found through text mining will often refer to compounds without specifying the stereoisomer. The database is accessible at http://stitch.embl.de/.
438.
MOCAT: A Metagenomics Assembly and Gene Prediction Toolkit.
Kultima JR, Sunagawa S, Li J, Chen W, Chen H, Mende DR, Arumugam M, Pan Q, Liu B, Qin J, Wang J, Bork P
Abstract + PDFMOCAT is a highly configurable, modular pipeline for fast, standardized processing of single or paired-end sequencing data generated by the Illumina platform. The pipeline uses state-of-the-art programs to quality control, map, and assemble reads from metagenomic samples sequenced at a depth of several billion base pairs, and predict protein-coding genes on assembled metagenomes. Mapping against reference databases allows for read extraction or removal, as well as abundance calculations. Relevant statistics for each processing step can be summarized into multi-sheet Excel documents and queryable SQL databases. MOCAT runs on UNIX machines and integrates seamlessly with the SGE and PBS queuing systems, commonly used to process large datasets. The open source code and modular architecture allow users to modify or exchange the programs that are utilized in the various processing steps. Individual processing steps and parameters were benchmarked and tested on artificial, real, and simulated metagenomes resulting in an improvement of selected quality metrics. MOCAT can be freely downloaded at http://www.bork.embl.de/mocat/.
437.
SMART 7: recent updates to the protein domain annotation resource.
2012 Jan 3; 40(Database issue): D302-5. Epub 2011 Nov 3; PubMed: 22053084.
Abstract + PDFSMART (Simple Modular Architecture Research Tool) is an online resource (http://smart.embl.de/) for the identification and annotation of protein domains and the analysis of protein domain architectures. SMART version 7 contains manually curated models for 1009 protein domains, 200 more than in the previous version. The current release introduces several novel features and a streamlined user interface resulting in a faster and more comfortable workflow. The underlying protein databases were greatly expanded, resulting in a 2-fold increase in number of annotated domains and features. The database of completely sequenced genomes now includes 1133 species, compared to 630 in the previous release. Domain architecture analysis results can now be exported and visualized through the iTOL phylogenetic tree viewer. 'metaSMART' was introduced as a novel subresource dedicated to the exploration and analysis of domain architectures in various metagenomics data sets. An advanced full text search engine was implemented, covering the complete annotations for SMART and Pfam domains, as well as the complete set of protein descriptions, allowing users to quickly find relevant information.
436.
Assessment of metagenomic assembly using simulated next generation sequencing data.
Abstract + PDFDue to the complexity of the protocols and a limited knowledge of the nature of microbial communities, simulating metagenomic sequences plays an important role in testing the performance of existing tools and data analysis methods with metagenomic data. We developed metagenomic read simulators with platform-specific (Sanger, pyrosequencing, Illumina) base-error models, and simulated metagenomes of differing community complexities. We first evaluated the effect of rigorous quality control on Illumina data. Although quality filtering removed a large proportion of the data, it greatly improved the accuracy and contig lengths of resulting assemblies. We then compared the quality-trimmed Illumina assemblies to those from Sanger and pyrosequencing. For the simple community (10 genomes) all sequencing technologies assembled a similar amount and accurately represented the expected functional composition. For the more complex community (100 genomes) Illumina produced the best assemblies and more correctly resembled the expected functional composition. For the most complex community (400 genomes) there was very little assembly of reads from any sequencing technology. However, due to the longer read length the Sanger reads still represented the overall functional composition reasonably well. We further examined the effect of scaffolding of contigs using paired-end Illumina reads. It dramatically increased contig lengths of the simple community and yielded minor improvements to the more complex communities. Although the increase in contig length was accompanied by increased chimericity, it resulted in more complete genes and a better characterization of the functional repertoire. The metagenomic simulators developed for this research are freely available.
435.
Deciphering a global network of functionally associated post-translational modifications.
2012 Jul 17; 8: 599. PubMed: 22806145.
Abstract + PDFVarious post-translational modifications (PTMs) fine-tune the functions of almost all eukaryotic proteins, and co-regulation of different types of PTMs has been shown within and between a number of proteins. Aiming at a more global view of the interplay between PTM types, we collected modifications for 13 frequent PTM types in 8 eukaryotes, compared their speed of evolution and developed a method for measuring PTM co-evolution within proteins based on the co-occurrence of sites across eukaryotes. As many sites are still to be discovered, this is a considerable underestimate, yet, assuming that most co-evolving PTMs are functionally associated, we found that PTM types are vastly interconnected, forming a global network that comprise in human alone >50 000 residues in about 6000 proteins. We predict substantial PTM type interplay in secreted and membrane-associated proteins and in the context of particular protein domains and short-linear motifs. The global network of co-evolving PTM types implies a complex and intertwined post-translational regulation landscape that is likely to regulate multiple functional states of many if not all eukaryotic proteins.
434.
eggNOG v3.0: orthologous groups covering 1133 organisms at 41 different taxonomic ranges.
Powell S, Szklarczyk D, Trachana K, Roth A, Kuhn M, Muller J, Arnold R, Rattei T, Letunic I, Doerks T, Jensen LJ, von Mering C, Bork P
2012 Jan 1; 40: D284-9. Epub 2011 Nov 16; PubMed: 22096231.
Abstract + PDFOrthologous relationships form the basis of most comparative genomic and metagenomic studies and are essential for proper phylogenetic and functional analyses. The third version of the eggNOG database (http://eggnog.embl.de) contains non-supervised orthologous groups constructed from 1133 organisms, doubling the number of genes with orthology assignment compared to eggNOG v2. The new release is the result of a number of improvements and expansions: (i) the underlying homology searches are now based on the SIMAP database; (ii) the orthologous groups have been extended to 41 levels of selected taxonomic ranges enabling much more fine-grained orthology assignments; and (iii) the newly designed web page is considerably faster with more functionality. In total, eggNOG v3 contains 721 801 orthologous groups, encompassing a total of 4 396 591 genes. Additionally, we updated 4873 and 4850 original COGs and KOGs, respectively, to include all 1133 organisms. At the universal level, covering all three domains of life, 101 208 orthologous groups are available, while the others are applicable at 40 more limited taxonomic ranges. Each group is amended by multiple sequence alignments and maximum-likelihood trees and broad functional descriptions are provided for 450 904 orthologous groups (62.5%).
433.
Cross-talk between phosphorylation and lysine acetylation in a genome-reduced bacterium.
van Noort V, Seebacher J, Bader S, Mohammed S, Vonkova I, Betts MJ, Kühner S, Kumar R, Maier T, O'Flaherty M, Rybin V, Schmeisky A, Yus E, Stülke J, Serrano L, Russell RB, Heck AJ, Bork P, Gavin AC
2012 Feb 28; 8: 571. PubMed: 22373819.
Abstract + PDFProtein post-translational modifications (PTMs) represent important regulatory states that when combined have been hypothesized to act as molecular codes and to generate a functional diversity beyond genome and transcriptome. We systematically investigate the interplay of protein phosphorylation with other post-transcriptional regulatory mechanisms in the genome-reduced bacterium Mycoplasma pneumoniae. Systematic perturbations by deletion of its only two protein kinases and its unique protein phosphatase identified not only the protein-specific effect on the phosphorylation network, but also a modulation of proteome abundance and lysine acetylation patterns, mostly in the absence of transcriptional changes. Reciprocally, deletion of the two putative N-acetyltransferases affects protein phosphorylation, confirming cross-talk between the two PTMs. The measured M. pneumoniae phosphoproteome and lysine acetylome revealed that both PTMs are very common, that (as in Eukaryotes) they often co-occur within the same protein and that they are frequently observed at interaction interfaces and in multifunctional proteins. The results imply previously unreported hidden layers of post-transcriptional regulation intertwining phosphorylation with lysine acetylation and other mechanisms that define the functional state of a cell.
432.
Prediction and identification of sequences coding for orphan enzymes using genomic and metagenomic neighbours.
Yamada T, Waller AS, Raes J, Zelezniak A, Perchat N, Perret A, Salanoubat M, Patil KR, Weissenbach J, Bork P
2012 May 8; 8: 581. PubMed: 22569339.
Abstract + PDFDespite the current wealth of sequencing data, one-third of all biochemically characterized metabolic enzymes lack a corresponding gene or protein sequence, and as such can be considered orphan enzymes. They represent a major gap between our molecular and biochemical knowledge, and consequently are not amenable to modern systemic analyses. As 555 of these orphan enzymes have metabolic pathway neighbours, we developed a global framework that utilizes the pathway and (meta)genomic neighbour information to assign candidate sequences to orphan enzymes. For 131 orphan enzymes (37% of those for which (meta)genomic neighbours are available), we associate sequences to them using scoring parameters with an estimated accuracy of 70%, implying functional annotation of 16 345 gene sequences in numerous (meta)genomes. As a case in point, two of these candidate sequences were experimentally validated to encode the predicted activity. In addition, we augmented the currently available genome-scale metabolic models with these new sequence-function associations and were able to expand the models by on average 8%, with a considerable change in the flux connectivity patterns and improved essentiality prediction.
431.
Transcription start site associated RNAs in bacteria.
Yus E, Güell M, Vivancos AP, Chen WH, Lluch-Senar M, Delgado J, Claude Gavin A, Bork P, Serrano L
2012 May 22; 8: 585. PubMed: 22617959.
Abstract + PDFHere, we report the genome-wide identification of small RNAs associated with transcription start sites (TSSs), termed tssRNAs, in Mycoplasma pneumoniae. tssRNAs were also found to be present in a different bacterial phyla, Escherichia coli. Similar to the recently identified promoter-associated tiny RNAs (tiRNAs) in eukaryotes, tssRNAs are associated with active promoters. Evidence suggests that these tssRNAs are distinct from previously described abortive transcription RNAs. ssRNAs have an average size of 45 bases and map exactly to the beginning of cognate full-length transcripts and to cryptic TSSs. Expression of bacterial tssRNAs requires factors other than the standard RNA polymerase holoenzyme. We have found that the RNA polymerase is halted at tssRNA positions in vivo, which may indicate that a pausing mechanism exists to prevent transcription in the absence of genes. These results suggest that small RNAs associated with TSSs could be a universal feature of bacterial transcription.
430.
The human small intestinal microbiota is driven by rapid uptake and conversion of simple carbohydrates.
Zoetendal EG, Raes J, van den Bogert B, Arumugam M, Booijink CC, Troost FJ, Bork P, Wels M, de Vos WM, Kleerebezem M
Abstract + PDFThe human gastrointestinal tract (GI tract) harbors a complex community of microbes. The microbiota composition varies between different locations in the GI tract, but most studies focus on the fecal microbiota, and that inhabiting the colonic mucosa. Consequently, little is known about the microbiota at other parts of the GI tract, which is especially true for the small intestine because of its limited accessibility. Here we deduce an ecological model of the microbiota composition and function in the small intestine, using complementing culture-independent approaches. Phylogenetic microarray analyses demonstrated that microbiota compositions that are typically found in effluent samples from ileostomists (subjects without a colon) can also be encountered in the small intestine of healthy individuals. Phylogenetic mapping of small intestinal metagenome of three different ileostomy effluent samples from a single individual indicated that Streptococcus sp., Escherichia coli, Clostridium sp. and high G+C organisms are most abundant in the small intestine. The compositions of these populations fluctuated in time and correlated to the short-chain fatty acids profiles that were determined in parallel. Comparative functional analysis with fecal metagenomes identified functions that are overrepresented in the small intestine, including simple carbohydrate transport phosphotransferase systems (PTS), central metabolism and biotin production. Moreover, metatranscriptome analysis supported high level in-situ expression of PTS and carbohydrate metabolic genes, especially those belonging to Streptococcus sp. Overall, our findings suggest that rapid uptake and fermentation of available carbohydrates contribute to maintaining the microbiota in the human small intestine.
2011 15 publication(s).
429.
Insight into structure and assembly of the nuclear pore complex by utilizing the genome of a eukaryotic thermophile.
Abstract + PDFDespite decades of research, the structure and assembly of the nuclear pore complex (NPC), which is composed of ∼30 nucleoporins (Nups), remain elusive. Here, we report the genome of the thermophilic fungus Chaetomium thermophilum (ct) and identify the complete repertoire of Nups therein. The thermophilic proteins show improved properties for structural and biochemical studies compared to their mesophilic counterparts, and purified ctNups enabled the reconstitution of the inner pore ring module that spans the width of the NPC from the anchoring membrane to the central transport channel. This module is composed of two large Nups, Nup192 and Nup170, which are flexibly bridged by short linear motifs made up of linker Nups, Nic96 and Nup53. This assembly illustrates how Nup interactions can generate structural plasticity within the NPC scaffold. Our findings therefore demonstrate the utility of the genome of a thermophilic eukaryote for studying complex molecular machines.
428.
Enterotypes of the human gut microbiome.
Arumugam M, Raes J, Pelletier E, Le Paslier D, Yamada T, Mende DR, Fernandes GR, Tap J, Bruls T, Batto JM, Bertalan M, Borruel N, Casellas F, Fernandez L, Gautier L, Hansen T, Hattori M, Hayashi T, Kleerebezem M, Kurokawa K, Leclerc M, Levenez F, Manichanh C, Nielsen HB, Nielsen T, Pons N, Poulain J, Qin J, Sicheritz-Ponten T, Tims S, Torrents D, Ugarte E, Zoetendal EG, Wang J, Guarner F, Pedersen O, de Vos WM, Brunak S, Doré J, Consortium M, Weissenbach J, Ehrlich SD, Bork P
Abstract + PDFOur knowledge of species and functional composition of the human gut microbiome is rapidly increasing, but it is still based on very few cohorts and little is known about variation across the world. By combining 22 newly sequenced faecal metagenomes of individuals from four countries with previously published data sets, here we identify three robust clusters (referred to as enterotypes hereafter) that are not nation or continent specific. We also confirmed the enterotypes in two published, larger cohorts, indicating that intestinal microbiota variation is generally stratified, not continuous. This indicates further the existence of a limited number of well-balanced host-microbial symbiotic states that might respond differently to diet and drug intake. The enterotypes are mostly driven by species composition, but abundant molecular functions are not necessarily provided by abundant species, highlighting the importance of a functional analysis to understand microbial communities. Although individual host properties such as body mass index, age, or gender cannot explain the observed enterotypes, data-driven marker genes or functional modules can be identified for each of these host properties. For example, twelve genes significantly correlate with age and three functional modules with the body mass index, hinting at a diagnostic potential of microbial markers.
426.
Network neighbors of drug targets contribute to drug side-effect similarity.
Abstract + PDFIn pharmacology, it is essential to identify the molecular mechanisms of drug action in order to understand adverse side effects. These adverse side effects have been used to infer whether two drugs share a target protein. However, side-effect similarity of drugs could also be caused by their target proteins being close in a molecular network, which as such could cause similar downstream effects. In this study, we investigated the proportion of side-effect similarities that is due to targets that are close in the network compared to shared drug targets. We found that only a minor fraction of side-effect similarities (5.8 %) are caused by drugs targeting proteins close in the network, compared to side-effect similarities caused by overlapping drug targets (64%). Moreover, these targets that cause similar side effects are more often in a linear part of the network, having two or less interactions, than drug targets in general. Based on the examples, we gained novel insight into the molecular mechanisms of side effects associated with several drug targets. Looking forward, such analyses will be extremely useful in the process of drug development to better understand adverse side effects.
425.
The ecoresponsive genome of Daphnia pulex.
Colbourne JK, Pfrender ME, Gilbert D, Thomas WK, Tucker A, Oakley TH, Tokishita S, Aerts A, Arnold GJ, Basu MK, Bauer DJ, Cáceres CE, Carmel L, Casola C, Choi JH, Detter JC, Dong Q, Dusheyko S, Eads BD, Fröhlich T, Geiler-Samerotte KA, Gerlach D, Hatcher P, Jogdeo S, Krijgsveld J, Kriventseva EV, Kültz D, Laforsch C, Lindquist E, Lopez J, Manak JR, Muller J, Pangilinan J, Patwardhan RP, Pitluck S, Pritham EJ, Rechtsteiner A, Rho M, Rogozin IB, Sakarya O, Salamov A, Schaack S, Shapiro H, Shiga Y, Skalitzky C, Smith Z, Souvorov A, Sung W, Tang Z, Tsuchiya D, Tu H, Vos H, Wang M, Wolf YI, Yamagata H, Yamada T, Ye Y, Shaw JR, Andrews J, Crease TJ, Tang H, Lucas SM, Robertson HM, Bork P, Koonin EV, Zdobnov EM, Grigoriev IV, Lynch M, Boore JL
Abstract + PDFWe describe the draft genome of the microcrustacean Daphnia pulex, which is only 200 megabases and contains at least 30,907 genes. The high gene count is a consequence of an elevated rate of gene duplication resulting in tandem gene clusters. More than a third of Daphnia's genes have no detectable homologs in any other available proteome, and the most amplified gene families are specific to the Daphnia lineage. The coexpansion of gene families interacting within metabolic pathways suggests that the maintenance of duplicated genes is not random, and the analysis of gene expression under different environmental conditions reveals that numerous paralogs acquire divergent expression patterns soon after duplication. Daphnia-specific genes, including many additional loci within sequenced regions that are otherwise devoid of annotations, are the most responsive genes to ecological challenges.
424.
Universally distributed single-copy genes indicate a constant rate of horizontal transfer.
Abstract + PDFSingle copy genes, universally distributed across the three domains of life and encoding mostly ancient parts of the translation machinery, are thought to be only rarely subjected to horizontal gene transfer (HGT). Indeed it has been proposed to have occurred in only a few genes and implies a rare, probably not advantageous event in which an ortholog displaces the original gene and has to function in a foreign context (orthologous gene displacement, OGD). Here, we have utilised an automatic method to identify HGT based on a conservative statistical approach capable of robustly assigning both donors and acceptors. Applied to 40 universally single copy genes we found that as many as 68 HGTs (implying OGDs) have occurred in these genes with a rate of 1.7 per family since the last universal common ancestor (LUCA). We examined a number of factors that have been claimed to be fundamental to HGT in general and tested their validity in the subset of universally distributed single copy genes. We found that differing functional constraints impact rates of OGD and the more evolutionarily distant the donor and acceptor, the less likely an OGD is to occur. Furthermore, species with larger genomes are more likely to be subjected to OGD. Most importantly, regardless of the trends above, the number of OGDs increases linearly with time, indicating a neutral, constant rate. This suggests that levels of HGT above this rate may be indicative of positively selected transfers that may allow niche adaptation or bestow other benefits to the recipient organism.
423.
Identifying single copy orthologs in metazoa.
2011 Dec; 7(12): e1002269. PubMed: 22144877.
Abstract + PDFThe identification of single copy (1-to-1) orthologs in any group of organisms is important for functional classification and phylogenetic studies. The Metazoa are no exception, but only recently has there been a wide-enough distribution of taxa with sufficiently high quality sequenced genomes to gain confidence in the wide-spread single copy status of a gene.Here, we present a phylogenetic approach for identifying overlooked single copy orthologs from multigene families and apply it to the Metazoa. Using 18 sequenced metazoan genomes of high quality we identified a robust set of 1,126 orthologous groups that have been retained in single copy since the last common ancestor of Metazoa. We found that the use of the phylogenetic procedure increased the number of single copy orthologs found by over a third more than standard taxon-count approaches. The orthologs represented a wide range of functional categories, expression profiles and levels of divergence.To demonstrate the value of our set of single copy orthologs, we used them to assess the completeness of 24 currently published metazoan genomes and 62 EST datasets. We found that the annotated genes in published genomes vary in coverage from 79% (Ciona intestinalis) to 99.8% (human) with an average of 92%, suggesting a value for the underlying error rate in genome annotation, and a strategy for identifying single copy orthologs in larger datasets. In contrast, the vast majority of EST datasets with no corresponding genome sequence available are largely under-sampled and probably do not accurately represent the actual genomic complement of the organisms from which they are derived.
422.
A Holistic Approach to Marine Eco-Systems Biology.
Karsenti E, Acinas SG, Bork P, Bowler C, De Vargas C, Raes J, Sullivan M, Arendt D, Benzoni F, Claverie JM, Follows M, Gorsky G, Hingamp P, Iudicone D, Jaillon O, Kandels-Lewis S, Krzic U, Not F, Ogata H, Pesant S, Reynaud EG, Sardet C, Sieracki ME, Speich S, Velayoudon D, Weissenbach J, Wincker P, the Tara Oceans Consortium
Abstract + PDFThe structure, robustness, and dynamics of ocean plankton ecosystems remain poorly understood due to sampling, analysis, and computational limitations. The Tara Oceans consortium organizes expeditions to help fill this gap at the global level.
421.
Interactive Tree Of Life v2: online annotation and display of phylogenetic trees made easy.
Letunic I, Bork P
2011 Jul 5; 39 Suppl 2: W475-8. Epub 2011 Apr 5; PubMed: 21470960.
Abstract + PDFInteractive Tree Of Life (http://itol.embl.de) is a web-based tool for the display, manipulation and annotation of phylogenetic trees. It is freely available and open to everyone. In addition to classical tree viewer functions, iTOL offers many novel ways of annotating trees with various additional data. Current version introduces numerous new features and greatly expands the number of supported data set types. Trees can be interactively manipulated and edited. A free personal account system is available, providing management and sharing of trees in user defined workspaces and projects. Export to various bitmap and vector graphics formats is supported. Batch access interface is available for programmatic access or inclusion of interactive trees into other web services.
420.
Toward molecular trait-based ecology through integration of biogeochemical, geographical and metagenomic data.
2011 Mar 15; 7: 473. PubMed: 21407210.
Abstract + PDFUsing metagenomic 'parts lists' to infer global patterns on microbial ecology remains a significant challenge. To deduce important ecological indicators such as environmental adaptation, molecular trait dispersal, diversity variation and primary production from the gene pool of an ecosystem, we integrated 25 ocean metagenomes with geographical, meteorological and geophysicochemical data. We find that climatic factors (temperature, sunlight) are the major determinants of the biomolecular repertoire of each sample and the main limiting factor on functional trait dispersal (absence of biogeographic provincialism). Molecular functional richness and diversity show a distinct latitudinal gradient peaking at 20°N and correlate with primary production. The latter can also be predicted from the molecular functional composition of an environmental sample. Together, our results show that the functional community composition derived from metagenomes is an important quantitative readout for molecular trait-based biogeography and ecology.
419.
The STRING database in 2011: functional interaction networks of proteins, globally integrated and scored.
Szklarczyk D, Franceschini A, Kuhn M, Simonovic M, Roth A, Minguez P, Doerks T, Stark M, Muller J, Bork P, Jensen LJ, von Mering C
2011 Jan 2; 39: D561-8. Epub 2010 Nov 2; PubMed: 21045058.
Abstract + PDFAn essential prerequisite for any systems-level understanding of cellular functions is to correctly uncover and annotate all functional interactions among proteins in the cell. Toward this goal, remarkable progress has been made in recent years, both in terms of experimental measurements and computational prediction techniques. However, public efforts to collect and present protein interaction information have struggled to keep up with the pace of interaction discovery, partly because protein-protein interaction information can be error-prone and require considerable effort to annotate. Here, we present an update on the online database resource Search Tool for the Retrieval of Interacting Genes (STRING); it provides uniquely comprehensive coverage and ease of access to both experimental as well as predicted interaction information. Interactions in STRING are provided with a confidence score, and accessory information such as protein domains and 3D structures is made available, all within a stable and consistent identifier space. New features in STRING include an interactive network viewer that can cluster networks on demand, updated on-screen previews of structural information including homology models, extensive data updates and strongly improved connectivity and integration with third-party resources. Version 9.0 of STRING covers more than 1100 completely sequenced organisms; the resource can be reached at http://string-db.org.
418.
Orthology prediction methods: A quality assessment using curated protein families.
Abstract + PDFThe increasing number of sequenced genomes has prompted the development of several automated orthology prediction methods. Tests to evaluate the accuracy of predictions and to explore biases caused by biological and technical factors are therefore required. We used 70 manually curated families to analyze the performance of five public methods in Metazoa. We analyzed the strengths and weaknesses of the methods and quantified the impact of biological and technical challenges. From the latter part of the analysis, genome annotation emerged as the largest single influencer, affecting up to 30% of the performance. Generally, most methods did well in assigning orthologous group but they failed to assign the exact number of genes for half of the groups. The publicly available benchmark set (http://eggnog.embl.de/orthobench/) should facilitate the improvement of current orthology assignment protocols, which is of utmost importance for many fields of biology and should be tackled by a broad scientific community.
417.
iPath2.0: interactive pathway explorer.
2011 Jul 5; 39 Suppl 2: W412-5. Epub 2011 May 5; PubMed: 21546551.
Abstract + PDFiPath2.0 is a web-based tool (http://pathways.embl.de) for the visualization and analysis of cellular pathways. Its primary map summarizes the metabolism in biological systems as annotated to date. Nodes in the map correspond to various chemical compounds and edges represent series of enzymatic reactions. In two other maps, iPath2.0 provides an overview of secondary metabolite biosynthesis and a hand-picked selection of important regulatory pathways and other functional modules, allowing a more general overview of protein functions in a genome or metagenome. iPath2.0's main interface is an interactive Flash-based viewer, which allows users to easily navigate and explore the complex pathway maps. In addition to the default pre-computed overview maps, iPath offers several data mapping tools. Users can upload various types of data and completely customize all nodes and edges of iPath2.0's maps. These customized maps give users an intuitive overview of their own data, guiding the analysis of various genomics and metagenomics projects.
416.
Minimum information about a marker gene sequence (MIMARKS) and minimum information about any (x) sequence (MIxS) specifications.
Yilmaz P, Kottmann R, Field D, Knight R, Cole JR, Amaral-Zettler L, Gilbert JA, Karsch-Mizrachi I, Johnston A, Cochrane G, Vaughan R, Hunter C, Park J, Morrison N, Rocca-Serra P, Sterk P, Arumugam M, Bailey M, Baumgartner L, Birren BW, Blaser MJ, Bonazzi V, Booth T, Bork P, Bushman FD, Buttigieg PL, Chain PS, Charlson E, Costello EK, Huot-Creasy H, Dawyndt P, Desantis T, Fierer N, Fuhrman JA, Gallery RE, Gevers D, Gibbs RA, Gil IS, Gonzalez A, Gordon JI, Guralnick R, Hankeln W, Highlander S, Hugenholtz P, Jansson J, Kau AL, Kelley ST, Kennedy J, Knights D, Koren O, Kuczynski J, Kyrpides N, Larsen R, Lauber CL, Legg T, Ley RE, Lozupone CA, Ludwig W, Lyons D, Maguire E, Methé BA, Meyer F, Muegge B, Nakielny S, Nelson KE, Nemergut D, Neufeld JD, Newbold LK, Oliver AE, Pace NR, Palanisamy G, Peplies J, Petrosino J, Proctor L, Pruesse E, Quast C, Raes J, Ratnasingham S, Ravel J, Relman DA, Assunta-Sansone S, Schloss PD, Schriml L, Sinha R, Smith MI, Sodergren E, Spor A, Stombaugh J, Tiedje JM, Ward DV, Weinstock GM, Wendel D, White O, Whiteley A, Wilke A, Wortman JR, Yatsunenko T, Glöckner FO
2011 May 6; 29(5): 415-20. Epub 2011 May 6; PubMed: 21552244.
Abstract + PDFHere we present a standard developed by the Genomic Standards Consortium (GSC) for reporting marker gene sequences-the minimum information about a marker gene sequence (MIMARKS). We also introduce a system for describing the environment from which a biological sample originates. The 'environmental packages' apply to any genome sequence of known origin and can be used in combination with MIMARKS and other GSC checklists. Finally, to establish a unified standard for describing sequence data and to provide a single point of entry for the scientific community to access and learn about GSC checklists, we present the minimum information about any (x) sequence (MIxS). Adoption of MIxS will enhance our ability to analyze natural genetic diversity documented by massive DNA sequencing efforts from myriad ecosystems in our ever-changing biosphere.
415.
Prediction of drug combinations by integrating molecular and pharmacological data.
2011 Dec; 7(12): e1002323. PubMed: 22219721.
Abstract + PDFCombinatorial therapy is a promising strategy for combating complex disorders due to improved efficacy and reduced side effects. However, screening new drug combinations exhaustively is impractical considering all possible combinations between drugs. Here, we present a novel computational approach to predict drug combinations by integrating molecular and pharmacological data. Specifically, drugs are represented by a set of their properties, such as their targets or indications. By integrating several of these features, we show that feature patterns enriched in approved drug combinations are not only predictive for new drug combinations but also provide insights into mechanisms underlying combinatorial therapy. Further analysis confirmed that among our top ranked predictions of effective combinations, 69% are supported by literature, while the others represent novel potential drug combinations. We believe that our proposed approach can help to limit the search space of drug combinations and provide a new way to effectively utilize existing drugs for new purposes.
2010 18 publication(s).
414.
A method and server for predicting damaging missense mutations.
2010 Apr; 7(4): 248-9. PubMed: 20354512.
PDF413.
SmashCommunity: A metagenomic annotation and analysis tool.
2010 Dec 1; 26(23): 2977-8. Epub 2010 Oct 19; PubMed: 20959381.
Abstract + PDFSUMMARY: SmashCommunity is a stand-alone metagenomic annotation and analysis pipeline suitable for data from Sanger and 454 sequencing technologies. It supports state-of-the-art software for essential metagenomic tasks such as assembly and gene prediction. It provides tools to estimate the quantitative phylogenetic and functional compositions of metagenomes, to compare compositions of multiple metagenomes and to produce intuitive visual representations of such analyses. AVAILABILITY: SmashCommunity is freely available at http://www.bork.embl.de/software/smash CONTACT: bork@embl.de.
412.
Ancient animal microRNAs and the evolution of tissue identity.
Christodoulou F, Raible F, Tomer R, Simakov O, Trachana K, Klaus S, Snyman H, Hannon GJ, Bork P, Arendt D
Abstract + PDFThe spectacular escalation in complexity in early bilaterian evolution correlates with a strong increase in the number of microRNAs. To explore the link between the birth of ancient microRNAs and body plan evolution, we set out to determine the ancient sites of activity of conserved bilaterian microRNA families in a comparative approach. We reason that any specific localization shared between protostomes and deuterostomes (the two major superphyla of bilaterian animals) should probably reflect an ancient specificity of that microRNA in their last common ancestor. Here, we investigate the expression of conserved bilaterian microRNAs in Platynereis dumerilii, a protostome retaining ancestral bilaterian features, in Capitella, another marine annelid, in the sea urchin Strongylocentrotus, a deuterostome, and in sea anemone Nematostella, representing an outgroup to the bilaterians. Our comparative data indicate that the oldest known animal microRNA, miR-100, and the related miR-125 and let-7 were initially active in neurosecretory cells located around the mouth. Other sets of ancient microRNAs were first present in locomotor ciliated cells, specific brain centres, or, more broadly, one of four major organ systems: central nervous system, sensory tissue, musculature and gut. These findings reveal that microRNA evolution and the establishment of tissue identities were closely coupled in bilaterian evolution. Also, they outline a minimum set of cell types and tissues that existed in the protostome-deuterostome ancestor.
411.
[Metagenomics of the intestinal microbiota: potential applications].
Dusko Ehrlich S, MetaHIT Consortium , Antolin M, Artiguenave F, Arumugam M, Batto JM, Bertalan M, Blottiere H, Bork P, Borruel N, Brechot C, Brunak S, Bruls T, Burgdorf KS, Cao J, Casellas F, Chervaux C, Colombel JF, Cultrone A, Doré J, Delorme C, Denariaz G, Dervyn R, Forte M, Friss C, Guarner F, Guchte Mv, Guedon E, Haimet F, Hansen T, Jamet A, Jian M, Juste C, Kaci G, Kleerebezem M, Knol J, Kristiansen K, Layec S, Le Roux K, Leclerc M, Le Paslier D, Levenez F, Li D, Li J, Li S, Li S, Li S, Li Y, Liang H, Mende D, Maguin E, Manichanh C, Minardi RM, Mrini C, Nielsen HB, Nielsen T, Oozeer R, Parkhill J, Pons N, Pedersen O, Pelletier E, Qin J, Raes J, Renault P, Rescigno M, Ruiqiang L, Sanchez N, Sicheritz-Ponten T, Tims S, Torrejon T, Turner K, Varela E, Vos Wd, Wang B, Wang J, Wang J, Weissenbach J, Winogradsky Y, Xie Y, Xu J, Yamada T, Yang H, Yu C, Zhang X, Zheng H, Zhu H, Zhou Y, Zoetendal E.
2010 Sep; 34 Suppl 1: S23-8. PubMed: 20889001.
AbstractA major challenge in the human metagenomics field is to identify associations of the bacterial genes and human phenotypes and act to modulate microbial populations in order to improve human health and wellbeing. MetaHIT project addresses this ambitious challenge by developing and integrating a number of necessary approaches within the context of the gut microbiome. Among the first results is the establishment of a broad catalog of the human gut microbial genes, which was achieved by an original application of the new generation sequencing technology. The catalog contains 3.3 million non-redundant genes, 150-fold more than the human genome equivalent and includes a large majority of the gut metagenomic sequences determined across three continents, Europe, America and Asia. Its content corresponds to some 1000 bacterial species, which likely represent a large fraction of species associated with humankind intestinal tract. The catalog enables development of the gene profiling approaches aiming to detect associations of bacterial genes and phenotypes. These should lead to the speedy development of diagnostic and prognostic tools and open avenues to reasoned approaches to the modulation of the individual's microbiota in order to optimize health and well-being.
410.
A systematic screen for protein-lipid interactions in Saccharomyces cerevisiae.
Gallego O, Betts MJ, Gvozdenovic-Jeremic J, Maeda K, Matetzki C, Aguilar-Gurrieri C, Beltran-Alvarez P, Bonn S, Fernández-Tornero C, Jensen LJ, Kuhn M, Trott J, Rybin V, Müller CW, Bork P, Kaksonen M, Russell RB, Gavin AC
2010 Nov 30; 6: 430. PubMed: 21119626.
Abstract + PDFProtein-metabolite networks are central to biological systems, but are incompletely understood. Here, we report a screen to catalog protein-lipid interactions in yeast. We used arrays of 56 metabolites to measure lipid-binding fingerprints of 172 proteins, including 91 with predicted lipid-binding domains. We identified 530 protein-lipid associations, the majority of which are novel. To show the data set's biological value, we studied further several novel interactions with sphingolipids, a class of conserved bioactive lipids with an elusive mode of action. Integration of live-cell imaging suggests new cellular targets for these molecules, including several with pleckstrin homology (PH) domains. Validated interactions with Slm1, a regulator of actin polarization, show that PH domains can have unexpected lipid-binding specificities and can act as coincidence sensors for both phosphatidylinositol phosphates and phosphorylated sphingolipids.
409.
High-resolution transcription atlas of the mitotic cell cycle in budding yeast.
Granovskaia MV, Jensen LJ, Ritchie ME, Toedling J, Ning Y, Bork P, Huber W, Steinmetz LM
2010 Mar 1; 11(3): R24. Epub 2010 Mar 1; PubMed: 20193063.
Abstract + PDFABSTRACT: BACKGROUND: Extensive transcription of non-coding RNAs has been detected in eukaryotic genomes and is thought to constitute an additional layer in the regulation of gene expression. Despite this role, their transcription through the cell cycle has not been studied; genome-wide approaches have only focused on protein-coding genes. To explore the complex transcriptome architecture underlying the budding yeast cell cycle, we used 8 bp tiling arrays to generate a 5 minute-resolution, strand-specific expression atlas of the whole genome. RESULTS: We discovered 523 antisense transcripts, of which 80 cycle or are located opposite periodically expressed mRNAs, 135 unannotated intergenic non-coding RNAs, of which 11 cycle, and 109 cell-cycle-regulated protein-coding genes that had not previously been shown to cycle. We detected periodic expression coupling of sense and antisense transcript pairs, including antisense transcripts opposite of key cell-cycle regulators, like FAR1 and TAF2. CONCLUSIONS: Our dataset presents the most comprehensive resource to date on gene expression during the budding yeast cell cycle, revealing both protein-coding and non-coding RNA periodicity of expression and the first that profiles non-annotated RNAs. It enables hypothesis-driven mechanistic studies concerning the functions of non-coding RNAs.
408.
SmashCell: A software framework for the analysis of single-cell amplified genome sequences.
2010 Dec 1; 26(23): 2979-80. Epub 2010 Oct 21; PubMed: 20966005.
Abstract + PDFSUMMARY: Recent advances in single-cell manipulation technology, whole genome amplification and high-throughput sequencing have now made it possible to sequence the genome of an individual cell. The bioinformatic analysis of these genomes however is far more complicated than the analysis of those generated using traditional, culture-based methods. In order to simplify this analysis we have developed SmashCell (Simple Metagenomics Analysis SHell-for sequences from single Cells). It is designed to automate the main steps in microbial genome analysis - assembly, gene prediction, functional annotation - in a way that allows parameter and algorithm exploration at each step in the process. It alsomanages the data created by these analyses and provides visualisation methods to allow rapid analysis of the results. AVAILABILITY: The SmashCell source code and a comprehensive manual are available at http://asiago.stanford.edu/SmashCell CONTACT: eoghanh@stanford.edu.
407.
Drug-Induced Regulation of Target Expression.
2010 Sep 9; 6(9): . PubMed: 20838579.
Abstract + PDFDrug perturbations of human cells lead to complex responses upon target binding. One of the known mechanisms is a (positive or negative) feedback loop that adjusts the expression level of the respective target protein. To quantify this mechanism systems-wide in an unbiased way, drug-induced differential expression of drug target mRNA was examined in three cell lines using the Connectivity Map. To overcome various biases in this valuable resource, we have developed a computational normalization and scoring procedure that is applicable to gene expression recording upon heterogeneous drug treatments. In 1290 drug-target relations, corresponding to 466 drugs acting on 167 drug targets studied, 8% of the targets are subject to regulation at the mRNA level. We confirmed systematically that in particular G-protein coupled receptors, when serving as known targets, are regulated upon drug treatment. We further newly identified drug-induced differential regulation of Lanosterol 14-alpha demethylase, Endoplasmin, DNA topoisomerase 2-alpha and Calmodulin 1. The feedback regulation in these and other targets is likely to be relevant for the success or failure of the molecular intervention.
406.
Ontologies in quantitative biology: a basis for comparison, integration, and discovery.
Jensen LJ, Bork P
Abstract + PDFAs biology is becoming a data-driven discipline, ontologies become increasingly important for systematically capturing the existing knowledge. This essay discusses current trends and how ontologies can also be used for discovery.
405.
A side effect resource to capture phenotypic effects of drugs.
2010; 6: 343. PubMed: 20087340.
Abstract + PDFThe molecular understanding of phenotypes caused by drugs in humans is essential for elucidating mechanisms of action and for developing personalized medicines. Side effects of drugs (also known as adverse drug reactions) are an important source of human phenotypic information, but so far research on this topic has been hampered by insufficient accessibility of data. Consequently, we have developed a public, computer-readable side effect resource (SIDER) that connects 888 drugs to 1450 side effect terms. It contains information on frequency in patients for one-third of the drug-side effect pairs. For 199 drugs, the side effect frequency of placebo administration could also be extracted. We illustrate the potential of SIDER with a number of analyses. The resource is freely available for academic research at http://sideeffects.embl.de.
404.
STITCH 2: an interaction network database for small molecules and proteins.
2010 Jan 6; 38: D552-6. Epub 2009 Nov 6; PubMed: 19897548.
Abstract + PDFOver the last years, the publicly available knowledge on interactions between small molecules and proteins has been steadily increasing. To create a network of interactions, STITCH aims to integrate the data dispersed over the literature and various databases of biological pathways, drug-target relationships and binding affinities. In STITCH 2, the number of relevant interactions is increased by incorporation of BindingDB, PharmGKB and the Comparative Toxicogenomics Database. The resulting network can be explored interactively or used as the basis for large-scale analyses. To facilitate links to other chemical databases, we adopt InChIKeys that allow identification of chemicals with a short, checksum-like string. STITCH 2.0 connects proteins from 630 organisms to over 74 000 different chemicals, including 2200 drugs. STITCH can be accessed at http://stitch.embl.de/.
403.
AQUA: Automated quality improvement for multiple sequence alignments.
2010 Jan 15; 26(2): 263-5. Epub 2009 Nov 19; PubMed: 19926669.
Abstract + PDFSUMMARY: Multiple Sequence Alignment (MSA) is a central tool in most modern biology studies. However, despite generations of valuable tools, human experts are still able to improve automatically generated MSAs. In an effort to automatically identify the most reliable MSA for a given protein family, we propose a very simple protocol, named AQUA for "Automated quality improvement for multiple sequence alignments". Our current implementation relies on 2 alignment programs (MUSCLE and MAFFT), one refinement program (RASCAL) and one assessment program (NORMD) but other programs could be incorporated at any of the 3 steps. AVAILABILITY: AQUA is implemented in Tcl/Tk and runs in command line on all platforms. The source code is available under the GNU GPL license. Source code, README and Supplementary data are available at http://www.bork.embl.de/Docu/AQUA. CONTACT: muller@embl.de, bork@embl.de.
402.
eggNOG v2.0: extending the evolutionary genealogy of genes with enhanced non-supervised orthologous groups, species and functional annotations.
Muller J, Szklarczyk D, Julien P, Letunic I, Roth A, Kuhn M, Powell S, von Mering C, Doerks T, Jensen LJ, Bork P
2010 Jan 9; 38: D190-5. Epub 2009 Nov 9; PubMed: 19900971.
Abstract + PDFThe identification of orthologous relationships forms the basis for most comparative genomics studies. Here, we present the second version of the eggNOG database, which contains orthologous groups (OGs) constructed through identification of reciprocal best BLAST matches and triangular linkage clustering. We applied this procedure to 630 complete genomes (529 bacteria, 46 archaea and 55 eukaryotes), which is a 2-fold increase relative to the previous version. The pipeline yielded 224 847 OGs, including 9724 extended versions of the original COG and KOG. We computed OGs for different levels of the tree of life; in addition to the species groups included in our first release (i.e. fungi, metazoa, insects, vertebrates and mammals), we have now constructed OGs for archaea, fishes, rodents and primates. We automatically annotate the non-supervised orthologous groups (NOGs) with functional descriptions, protein domains, and functional categories as defined initially for the COG/KOG database. In-depth analysis is facilitated by precomputed high-quality multiple sequence alignments and maximum-likelihood trees for each of the available OGs. Altogether, eggNOG covers 2 242 035 proteins (built from 2 590 259 proteins) and provides a broad functional description for at least 1 966 709 (88%) of them. Users can access the complete set of orthologous groups via a web interface at: http://eggnog.embl.de.
401.
Functional and evolutionary insights from the genomes of three parasitoid Nasonia species.
Nasonia Genome Working Group , Werren JH, Richards S, Desjardins CA, Niehuis O, Gadau J, Colbourne JK, Beukeboom LW, Desplan C, Elsik CG, Grimmelikhuijzen CJ, Kitts P, Lynch JA, Murphy T, Oliveira DC, Smith CD, van de Zande L, Worley KC, Zdobnov EM, Aerts M, Albert S, Anaya VH, Anzola JM, Barchuk AR, Behura SK, Bera AN, Berenbaum MR, Bertossa RC, Bitondi MM, Bordenstein SR, Bork P, Bornberg-Bauer E, Brunain M, Cazzamali G, Chaboub L, Chacko J, Chavez D, Childers CP, Choi JH, Clark ME, Claudianos C, Clinton RA, Cree AG, Cristino AS, Dang PM, Darby AC, de Graaf DC, Devreese B, Dinh HH, Edwards R, Elango N, Elhaik E, Ermolaeva O, Evans JD, Foret S, Fowler GR, Gerlach D, Gibson JD, Gilbert DG, Graur D, Gründer S, Hagen DE, Han Y, Hauser F, Hultmark D, Hunter HC, Hurst GD, Jhangian SN, Jiang H, Johnson RM, Jones AK, Junier T, Kadowaki T, Kamping A, Kapustin Y, Kechavarzi B, Kim J, Kim J, Kiryutin B, Koevoets T, Kovar CL, Kriventseva EV, Kucharski R, Lee H, Lee SL, Lees K, Lewis LR, Loehlin DW, Logsdon JM, Lopez JA, Lozado RJ, Maglott D, Maleszka R, Mayampurath A, Mazur DJ, McClure MA, Moore AD, Morgan MB, Muller J, Munoz-Torres MC, Muzny DM, Nazareth LV, Neupert S, Nguyen NB, Nunes FM, Oakeshott JG, Okwuonu GO, Pannebakker BA, Pejaver VR, Peng Z, Pratt SC, Predel R, Pu LL, Ranson H, Raychoudhury R, Rechtsteiner A, Reese JT, Reid JG, Riddle M, Robertson HM, Romero-Severson J, Rosenberg M, Sackton TB, Sattelle DB, Schlüns H, Schmitt T, Schneider M, Schüler A, Schurko AM, Shuker DM, Simões ZL, Sinha S, Smith Z, Solovyev V, Souvorov A, Springauf A, Stafflinger E, Stage DE, Stanke M, Tanaka Y, Telschow A, Trent C, Vattathil S, Verhulst EC, Viljakainen L, Wanner KW, Waterhouse RM, Whitfield JB, Wilkes TE, Williamson M, Willis JH, Wolschin F, Wyder S, Yamada T, Yi SV, Zecher CN, Zhang L, Gibbs RA
Abstract + PDFWe report here genome sequences and comparative analyses of three closely related parasitoid wasps: Nasonia vitripennis, N. giraulti, and N. longicornis. Parasitoids are important regulators of arthropod populations, including major agricultural pests and disease vectors, and Nasonia is an emerging genetic model, particularly for evolutionary and developmental genetics. Key findings include the identification of a functional DNA methylation tool kit; hymenopteran-specific genes including diverse venoms; lateral gene transfers among Pox viruses, Wolbachia, and Nasonia; and the rapid evolution of genes involved in nuclear-mitochondrial interactions that are implicated in speciation. Newly developed genome resources advance Nasonia for genetic research, accelerate mapping and cloning of quantitative trait loci, and will ultimately provide tools and knowledge for further increasing the utility of parasitoids as pest insect-control agents.
400.
A human gut microbial gene catalogue established by metagenomic sequencing.
Qin J, Li R, Raes J, Arumugam M, Burgdorf KS, Manichanh C, Nielsen T, Pons N, Levenez F, Yamada T, Mende DR, Li J, Xu J, Li S, Li D, Cao J, Wang B, Liang H, Zheng H, Xie Y, Tap J, Lepage P, Bertalan M, Batto JM, Hansen T, Le Paslier D, Linneberg A, Nielsen HB, Pelletier E, Renault P, Sicheritz-Ponten T, Turner K, Zhu H, Yu C, Li S, Jian M, Zhou Y, Li Y, Zhang X, Li S, Qin N, Yang H, Wang J, Brunak S, Doré J, Guarner F, Kristiansen K, Pedersen O, Parkhill J, Weissenbach J, Bork P, Ehrlich SD, Wang J, MetaHIT Consortium
Abstract + PDFTo understand the impact of gut microbes on human health and well-being it is crucial to assess their genetic potential. Here we describe the Illumina-based metagenomic sequencing, assembly and characterization of 3.3 million non-redundant microbial genes, derived from 576.7 gigabases of sequence, from faecal samples of 124 European individuals. The gene set, approximately 150 times larger than the human gene complement, contains an overwhelming majority of the prevalent (more frequent) microbial genes of the cohort and probably includes a large proportion of the prevalent human intestinal microbial genes. The genes are largely shared among individuals of the cohort. Over 99% of the genes are bacterial, indicating that the entire cohort harbours between 1,000 and 1,150 prevalent bacterial species and each individual at least 160 such species, which are also largely shared. We define and describe the minimal gut metagenome and the minimal gut bacterial genome in terms of functions present in all individuals and most bacteria, respectively.
399.
A network of conserved co-occurring motifs for the regulation of alternative splicing.
2010 Dec 11; 38(22): 7916-26. Epub 2010 Aug 11; PubMed: 20702423.
Abstract + PDFCis-acting short sequence motifs play important roles in alternative splicing. It is now possible to identify such sequence motifs as conserved sequence patterns in genome sequence alignments. Here, we report the systematic search for motifs in the neighboring introns of alternatively spliced exons by using comparative analysis of mammalian genome alignments. We identified 11 conserved sequence motifs that might be involved in the regulation of alternative splicing. These motifs are not only significantly overrepresented near alternatively spliced exons, but they also co-occur with each other, thus, forming a network of cis-elements, likely to be the basis for context-dependent regulation. Based on this finding, we applied the motif co-occurrence to predict alternatively skipped exons. We verified exon skipping in 29 cases out of 118 predictions (25%) by EST and mRNA sequences in the databases. For the predictions not verified by the database sequences, we confirmed exon skipping in 10 additional cases by using both RT-PCR experiments and the publicly available RNA-Seq data. These results indicate that even more alternative splicing events will be found with the progress of large-scale and high-throughput analyses for various tissue samples and developmental stages.
398.
Evolution and regulation of cellular periodic processes: a role for paralogues.
Abstract + PDFSeveral cyclic processes take place within a single organism. For example, the cell cycle is coordinated with the 24 h diurnal rhythm in animals and plants, and with the 40 min ultradian rhythm in budding yeast. To examine the evolution of periodic gene expression during these processes, we performed the first systematic comparison in three organisms (Homo sapiens, Arabidopsis thaliana and Saccharomyces cerevisiae) by using public microarray data. We observed that although diurnal-regulated and ultradian-regulated genes are not generally cell-cycle-regulated, they tend to have cell-cycle-regulated paralogues. Thus, diverged temporal expression of paralogues seems to facilitate cellular orchestration under different periodic stimuli. Lineage-specific functional repertoires of periodic-associated paralogues imply that this mode of regulation might have evolved independently in several organisms.
397.
SelTarbase, a database of human mononucleotide-microsatellite mutations and their potential impact to tumorigenesis and immunology.
Woerner SM, Yuan YP, Benner A, Korff S, von Knebel Doeberitz M, Bork P
2010 Jan 9; 38: D682-9. Epub 2009 Oct 9; PubMed: 19820113.
Abstract + PDFAbout 15% of human colorectal cancers and, at varying degrees, other tumor entities as well as nearly all tumors related to Lynch syndrome are hallmarked by microsatellite instability (MSI) as a result of a defective mismatch repair system. The functional impact of resulting mutations depends on their genomic localization. Alterations within coding mononucleotide repeat tracts (MNRs) can lead to protein truncation and formation of neopeptides, whereas alterations within untranslated MNRs can alter transcription level or transcript stability. These mutations may provide selective advantage or disadvantage to affected cells. They may further concern the biology of microsatellite unstable cells, e.g. by generating immunogenic peptides induced by frameshifts mutations. The Selective Targets database (http://www.seltarbase.org) is a curated database of a growing number of public MNR mutation data in microsatellite unstable human tumors. Regression calculations for various MSI-H tumor entities indicating statistically deviant mutation frequencies predict TGFBR2, BAX, ACVR2A and others that are shown or highly suspected to be involved in MSI tumorigenesis. Many useful tools for further analyzing genomic DNA, derived wild-type and mutated cDNAs and peptides are integrated. A comprehensive database of all human coding, untranslated, non-coding RNA- and intronic MNRs (MNR_ensembl) is also included. Herewith, SelTarbase presents as a plenty instrument for MSI-carcinogenesis-related research, diagnostics and therapy.
2009 11 publication(s).
396.
Quantifying environmental adaptation of metabolic pathways in metagenomics.
Gianoulis TA, Raes J, Patel PV, Bjornson R, Korbel JO, Letunic I, Yamada T, Paccanaro A, Jensen LJ, Snyder M, Bork P, Gerstein MB
2009 Feb 3; 106(5): 1374-9. Epub 2009 Jan 22; PubMed: 19164758.
Abstract + PDFRecently, approaches have been developed to sample the genetic content of heterogeneous environments (metagenomics). However, by what means these sequences link distinct environmental conditions with specific biological processes is not well understood. Thus, a major challenge is how the usage of particular pathways and subnetworks reflects the adaptation of microbial communities across environments and habitats-i.e., how network dynamics relates to environmental features. Previous research has treated environments as discrete, somewhat simplified classes (e.g., terrestrial vs. marine), and searched for obvious metabolic differences among them (i.e., treating the analysis as a typical classification problem). However, environmental differences result from combinations of many factors, which often vary only slightly. Therefore, we introduce an approach that employs correlation and regression to relate multiple, continuously varying factors defining an environment to the extent of particular microbial pathways present in a geographic site. Moreover, rather than looking only at individual correlations (one-to-one), we adapted canonical correlation analysis and related techniques to define an ensemble of weighted pathways that maximally covaries with a combination of environmental variables (many-to-many), which we term a metabolic footprint. Applied to available aquatic datasets, we identified footprints predictive of their environment that can potentially be used as biosensors. For example, we show a strong multivariate correlation between the energy-conversion strategies of a community and multiple environmental gradients (e.g., temperature). Moreover, we identified covariation in amino acid transport and cofactor synthesis, suggesting that limiting amounts of cofactor can (partially) explain increased import of amino acids in nutrient-limited conditions.
395.
Transcriptome complexity in a genome-reduced bacterium.
Güell M, van Noort V, Yus E, Chen WH, Leigh-Bell J, Michalodimitrakis K, Yamada T, Arumugam M, Doerks T, Kühner S, Rode M, Suyama M, Schmidt S, Gavin AC, Bork P, Serrano L
Abstract + PDFTo study basic principles of transcriptome organization in bacteria, we analyzed one of the smallest self-replicating organisms, Mycoplasma pneumoniae. We combined strand-specific tiling arrays, complemented by transcriptome sequencing, with more than 252 spotted arrays. We detected 117 previously undescribed, mostly noncoding transcripts, 89 of them in antisense configuration to known genes. We identified 341 operons, of which 139 are polycistronic; almost half of the latter show decaying expression in a staircase-like manner. Under various conditions, operons could be divided into 447 smaller transcriptional units, resulting in many alternative transcripts. Frequent antisense transcripts, alternative transcripts, and multiple regulators per gene imply a highly dynamic transcriptome, more similar to that of eukaryotes than previously thought.
394.
InterPro: the integrative protein signature database.
Hunter S, Apweiler R, Attwood TK, Bairoch A, Bateman A, Binns D, Bork P, Das U, Daugherty L, Duquenne L, Finn RD, Gough J, Haft D, Hulo N, Kahn D, Kelly E, Laugraud A, Letunic I, Lonsdale D, Lopez R, Madera M, Maslen J, McAnulla C, McDowall J, Mistry J, Mitchell A, Mulder N, Natale D, Orengo C, Quinn AF, Selengut JD, Sigrist CJ, Thimma M, Thomas PD, Valentin F, Wilson D, Wu CH, Yeats C
2009 Jan 21; 37: D211-5. Epub 2008 Oct 21; PubMed: 18940856.
Abstract + PDFThe InterPro database (http://www.ebi.ac.uk/interpro/) integrates together predictive models or 'signatures' representing protein domains, families and functional sites from multiple, diverse source databases: Gene3D, PANTHER, Pfam, PIRSF, PRINTS, ProDom, PROSITE, SMART, SUPERFAMILY and TIGRFAMs. Integration is performed manually and approximately half of the total approximately 58 000 signatures available in the source databases belong to an InterPro entry. Recently, we have started to also display the remaining un-integrated signatures via our web interface. Other developments include the provision of non-signature data, such as structural data, in new XML files on our FTP site, as well as the inclusion of matchless UniProtKB proteins in the existing match XML files. The web interface has been extended and now links out to the ADAN predicted protein-protein interaction database and the SPICE and Dasty viewers. The latest public release (v18.0) covers 79.8% of UniProtKB (v14.1) and consists of 16 549 entries. InterPro data may be accessed either via the web address above, via web services, by downloading files by anonymous FTP or by using the InterProScan search software (http://www.ebi.ac.uk/Tools/InterProScan/).
393.
STRING 8--a global view on proteins and their functional interactions in 630 organisms.
Jensen LJ, Kuhn M, Stark M, Chaffron S, Creevey CJ, Muller J, Doerks T, Julien P, Roth A, Simonovic M, Bork P, von Mering C
2009 Jan 21; 37: D412-6. Epub 2008 Oct 21; PubMed: 18940858.
Abstract + PDFFunctional partnerships between proteins are at the core of complex cellular phenotypes, and the networks formed by interacting proteins provide researchers with crucial scaffolds for modeling, data reduction and annotation. STRING is a database and web resource dedicated to protein-protein interactions, including both physical and functional interactions. It weights and integrates information from numerous sources, including experimental repositories, computational prediction methods and public text collections, thus acting as a meta-database that maps all interaction evidence onto a common set of genomes and proteins. The most important new developments in STRING 8 over previous releases include a URL-based programming interface, which can be used to query STRING from other resources, improved interaction prediction via genomic neighborhood in prokaryotes, and the inclusion of protein structures. Version 8.0 of STRING covers about 2.5 million proteins from 630 organisms, providing the most comprehensive view on protein-protein interactions currently available. STRING can be reached at http://string-db.org/.
392.
Sequence-based feature prediction and annotation of proteins.
Juncker AS, Jensen LJ, Pierleoni A, Bernsel A, Tress ML, Bork P, von Heijne G, Valencia A, Ouzounis CA, Casadio R, Brunak S
2009 Feb 2; 10(2): 206. Epub 2009 Feb 2; PubMed: 19226438.
Abstract + PDFABSTRACT: A recent trend in computational methods for annotation of protein function is that many prediction tools are combined in complex workflows and pipelines to facilitate the analysis of feature combinations, for example, the entire repertoire of kinase-binding motifs in the human proteome.
391.
ASTD: The Alternative Splicing and Transcript Diversity database.
Koscielny G, Texier VL, Gopalakrishnan C, Kumanduri V, Riethoven JJ, Nardone F, Stanley E, Fallsehr C, Hofmann O, Kull M, Harrington ED, Boue S, Eyras E, Plass M, Lopez F, Ritchie W, Moucadel V, Ara T, Pospisil H, Herrmann A, G Reich J, Guigó R, Bork P, Doeberitz MV, Vilo J, Hide W, Apweiler R, Thanaraj TA, Gautheret D
Abstract + PDFThe Alternative Splicing and Transcript Diversity database (ASTD) gives access to a vast collection of alternative transcripts that integrate transcription initiation, polyadenylation and splicing variant data. Alternative transcripts are derived from the mapping of transcribed sequences to the complete human, mouse and rat genomes using an extension of the computational pipeline developed for the ASD (Alternative Splicing Database) and ATD (Alternative Transcript Diversity) databases, which are now superseded by ASTD. For the human genome, ASTD identifies splicing variants, transcription initiation variants and polyadenylation variants in 68%, 68% and 62% of the gene set, respectively, consistent with current estimates for transcription variation. Users can access ASTD through a variety of browsing and query tools, including expression state-based queries for the identification of tissue-specific isoforms. Participating labs have experimentally validated a subset of ASTD-predicted alternative splice forms and alternative polyadenylation forms that were not previously reported. The ASTD database is accessed at http://www.ebi.ac.uk/astd.
390.
Proteome organization in a genome-reduced bacterium.
Kühner S, van Noort V, Betts MJ, Leo-Macias A, Batisse C, Rode M, Yamada T, Maier T, Bader S, Beltran-Alvarez P, Castaño-Diez D, Chen WH, Devos DP, Güell M, Norambuena T, Racke I, Rybin V, Schmidt A, Yus E, Aebersold R, Herrmann R, Böttcher B, Frangakis AS, Russell RB, Serrano L, Bork P, Gavin AC
Abstract + PDFThe genome of Mycoplasma pneumoniae is among the smallest found in self-replicating organisms. To study the basic principles of bacterial proteome organization, we used tandem affinity purification-mass spectrometry (TAP-MS) in a proteome-wide screen. The analysis revealed 62 homomultimeric and 116 heteromultimeric soluble protein complexes, of which the majority are novel. About a third of the heteromultimeric complexes show higher levels of proteome organization, including assembly into larger, multiprotein complex entities, suggesting sequential steps in biological processes, and extensive sharing of components, implying protein multifunctionality. Incorporation of structural models for 484 proteins, single-particle electron microscopy, and cellular electron tomograms provided supporting structural details for this proteome organization. The data set provides a blueprint of the minimal cellular machinery required for life.
389.
SMART 6: recent updates and new developments.
2009 Jan 31; 37: D229-32. Epub 2008 Oct 31; PubMed: 18978020.
Abstract + PDFSimple modular architecture research tool (SMART) is an online tool (http://smart.embl.de/) for the identification and annotation of protein domains. It provides a user-friendly platform for the exploration and comparative study of domain architectures in both proteins and genes. The current release of SMART contains manually curated models for 784 protein domains. Recent developments were focused on further data integration and improving user friendliness. The underlying protein database based on completely sequenced genomes was greatly expanded and now includes 630 species, compared to 191 in the previous release. As an initial step towards integrating information on biological pathways into SMART, our domain annotations were extended with data on metabolic pathways and links to several pathways resources. The interaction network view was completely redesigned and is now available for more than 2 million proteins. In addition to the standard web access to the database, users can now query SMART using distributed annotation system (DAS) or through a simple object access protocol (SOAP) based web service.
388.
Discovering functional novelty in metagenomes: examples from light-mediated processes.
2009 Jan 10; 191(1): 32-41. Epub 2008 Oct 10; PubMed: 18849420.
Abstract + PDFThe emerging coverage of diverse habitats by metagenomic shotgun data opens new avenues of discovering functional novelty using computational tools. Here, we apply three different concepts for predicting novel functions within light-mediated microbial pathways in five diverse environments. Using phylogenetic approaches, we discovered two novel deep-branching subfamilies of photolyases (involved in light-mediated repair) distributed abundantly in high-UV environments. Using neighborhood approaches, we were able to assign to BLUF domain-containing proteins (involved in light-sensing) seven novel functional partners in luciferase synthesis, nitrogen metabolism, and quorum sensing. Finally, by domain analysis, we predict for RcaE proteins (involved in chromatic adaptation) sixteen novel domain architectures that indicate novel functionalities in habitats with little or no light. Quantification of protein abundance in the various environments supports our findings that bacteria utilize light for sensing, repair, and adaptation far more widely than previously thought. While the discoveries illustrate the opportunities in function discovery, we also discuss the immense conceptual and practical challenges that come along with this new type of data.
387.
Evolution of biomolecular networks - lessons from metabolic and protein interactions.
Yamada T, Bork P
2009 Nov; 10(11): 791-803. PubMed: 19851337.
Abstract + PDFDespite only becoming popular at the beginning of this decade, biomolecular networks are now frameworks that facilitate many discoveries in molecular biology. The nodes of these networks are usually proteins (specifically enzymes in metabolic networks), whereas the links (or edges) are their interactions with other molecules. These networks are made up of protein-protein interactions or enzyme-enzyme interactions through shared metabolites in the case of metabolic networks. Evolutionary analysis has revealed that changes in the nodes and links in protein-protein interaction and metabolic networks are subject to different selection pressures owing to distinct topological features. However, many evolutionary constraints can be uncovered only if temporal and spatial aspects are included in the network analysis.
386.
Impact of genome reduction on bacterial metabolism and its regulation.
Yus E, Maier T, Michalodimitrakis K, van Noort V, Yamada T, Chen WH, Wodke JA, Güell M, Martínez S, Bourgeois R, Kühner S, Raineri E, Letunic I, Kalinina OV, Rode M, Herrmann R, Gutiérrez-Gallego R, Russell RB, Gavin AC, Bork P, Serrano L
Abstract + PDFTo understand basic principles of bacterial metabolism organization and regulation, but also the impact of genome size, we systematically studied one of the smallest bacteria, Mycoplasma pneumoniae. A manually curated metabolic network of 189 reactions catalyzed by 129 enzymes allowed the design of a defined, minimal medium with 19 essential nutrients. More than 1300 growth curves were recorded in the presence of various nutrient concentrations. Measurements of biomass indicators, metabolites, and (13)C-glucose experiments provided information on directionality, fluxes, and energetics; integration with transcription profiling enabled the global analysis of metabolic regulation. Compared with more complex bacteria, the M. pneumoniae metabolic network has a more linear topology and contains a higher fraction of multifunctional enzymes; general features such as metabolite concentrations, cellular energetics, adaptability, and global gene expression responses are similar, however.
2008 29 publication(s).
385.
Drug target identification using side-effect similarity.
Abstract + PDFTargets for drugs have so far been predicted on the basis of molecular or cellular features, for example, by exploiting similarity in chemical structure or in activity across cell lines. We used phenotypic side-effect similarities to infer whether two drugs share a target. Applied to 746 marketed drugs, a network of 1018 side effect-driven drug-drug relations became apparent, 261 of which are formed by chemically dissimilar drugs from different therapeutic indications. We experimentally tested 20 of these unexpected drug-drug relations and validated 13 implied drug-target relations by in vitro binding assays, of which 11 reveal inhibition constants equal to less than 10 micromolar. Nine of these were tested and confirmed in cell assays, documenting the feasibility of using phenotypic information to infer molecular interactions and hinting at new uses of marketed drugs.
384.
A computational screen for type I polyketide synthases in metagenomics shotgun data.
Abstract + PDFBACKGROUND: Polyketides are a diverse group of biotechnologically important secondary metabolites that are produced by multi domain enzymes called polyketide synthases (PKS). METHODOLOGY/PRINCIPAL FINDINGS: We have estimated frequencies of type I PKS (PKS I) - a PKS subgroup - in natural environments by using Hidden-Markov-Models of eight domains to screen predicted proteins from six metagenomic shotgun data sets. As the complex PKS I have similarities to other multi-domain enzymes (like those for the fatty acid biosynthesis) we increased the reliability and resolution of the dataset by maximum-likelihood trees. The combined information of these trees was then used to discriminate true PKS I domains from evolutionary related but functionally different ones. We were able to identify numerous novel PKS I proteins, the highest density of which was found in Minnesota farm soil with 136 proteins out of 183,536 predicted genes. We also applied the protocol to UniRef database to improve the annotation of proteins with so far unknown function and identified some new instances of horizontal gene transfer. CONCLUSIONS/SIGNIFICANCE: The screening approach proved powerful in identifying PKS I sequences in large sequence data sets and is applicable to many other protein families.
383.
A Nitrile Hydratase in the Eukaryote Monosiga brevicollis.
Abstract + PDFBacterial nitrile hydratase (NHases) are important industrial catalysts and waste water remediation tools. In a global computational screening of conventional and metagenomic sequence data for NHases, we detected the two usually separated NHase subunits fused in one protein of the choanoflagellate Monosiga brevicollis, a recently sequenced unicellular model organism from the closest sister group of Metazoa. This is the first time that an NHase is found in eukaryotes and the first time it is observed as a fusion protein. The presence of an intron, subunit fusion and expressed sequence tags covering parts of the gene exclude contamination and suggest a functional gene. Phylogenetic analyses and genomic context imply a probable ancient horizontal gene transfer (HGT) from proteobacteria. The newly discovered NHase might open biotechnological routes due to its unconventional structure, its new type of host and its apparent integration into eukaryotic protein networks.
382.
Protein-protein interactions: analysis and prediction.
Frishman D, Albrecht M, Blankenburg H, Bork P, Harrington ED, Hermjakob H, Jensen LJ, Juan DA, Lengauer T, Pagel P, Schächter V, Valencia A
In: Frishman D and Valencia A (Editors): Modern genome annotation pp.353–412. BID: 20.
ISBN: 978-3-211-75122-0 Publisher: Springer
381.
SuperTarget and Matador: resources for exploring drug-target relationships.
Günther S, Kuhn M, Dunkel M, Campillos M, Senger C, Petsalaki E, Ahmed J, Urdiales EG, Gewiess A, Jensen LJ, Schneider R, Skoblo R, Russell RB, Bourne PE, Bork P, Preissner R
2008 Jan 16; 36: D919-22. Epub 2007 Oct 16; PubMed: 17942422.
Abstract + PDFThe molecular basis of drug action is often not well understood. This is partly because the very abundant and diverse information generated in the past decades on drugs is hidden in millions of medical articles or textbooks. Therefore, we developed a one-stop data warehouse, SuperTarget that integrates drug-related information about medical indication areas, adverse drug effects, drug metabolization, pathways and Gene Ontology terms of the target proteins. An easy-to-use query interface enables the user to pose complex queries, for example to find drugs that target a certain pathway, interacting drugs that are metabolized by the same cytochrome P450 or drugs that target the same protein but are metabolized by different enzymes. Furthermore, we provide tools for 2D drug screening and sequence comparison of the targets. The database contains more than 2500 target proteins, which are annotated with about 7300 relations to 1500 drugs; the vast majority of entries have pointers to the respective literature source. A subset of these drugs has been annotated with additional binding information and indirect interactions and is available as a separate resource called Matador. SuperTarget and Matador are available at http://insilico.charite.de/supertarget and http://matador.embl.de.
380.
Sircah: A tool for the detection and visualisation of alternative transcripts.
Harrington ED, Bork P
2008 Sep 1; 24(17): 1959-60. Epub 2008 Jul 17; PubMed: 18635569.
Abstract + PDFSUMMARY: Sircah is a flexible tool for the detection, analysis and visualisation of alternative transcripts. It takes as input gene models or spliced alignments and creates a database of alternative transcription events: alternative transcription initiation and polyadenylation, alternative 3' and 5' splice-site usage, skipped exons and retained introns. The results can be visualised in a variety of ways, allowing the creation of publication quality images. RESULTS: AVAILABILITY: The Sircah is available for download under a creative commons license along with additional documentation and a tutorial from http://www.bork.embl.de/Sircah. CONTACT: bork@embl.de.
379.
Predicting biological networks from genomic data.
Abstract + PDFContinuing improvements in DNA sequencing technologies are providing us with vast amounts of genomic data from an ever-widening range of organisms. The resulting challenge for bioinformatics is to interpret this deluge of data and place it back into its biological context. Biological networks provide a conceptual framework with which we can describe part of this context, namely the different interactions that occur between the molecular components of a cell. Here, we review the computational methods available to predict biological networks from genomic sequence data and discuss how they relate to high-throughput experimental methods.
378.
4DXpress: a database for cross-species expression pattern comparisons.
Haudry Y, Berube H, Letunic I, Weeber PD, Gagneur J, Girardot C, Kapushesky M, Arendt D, Bork P, Brazma A, Furlong E, Wittbrodt J, Henrich T
2008 Jan 17; 36: D847-53. Epub 2007 Dec 17; PubMed: 17916571.
Abstract + PDFIn the major animal model species like mouse, fish or fly, detailed spatial information on gene expression over time can be acquired through whole mount in situ hybridization experiments. In these species, expression patterns of many genes have been studied and data has been integrated into dedicated model organism databases like ZFIN for zebrafish, MEPD for medaka, BDGP for Drosophila or GXD for mouse. However, a central repository that allows users to query and compare gene expression patterns across different species has not yet been established. Therefore, we have integrated expression patterns for zebrafish, Drosophila, medaka and mouse into a central public repository called 4DXpress (expression database in four dimensions). Users can query anatomy ontology-based expression annotations across species and quickly jump from one gene to the orthologues in other species. Genes are linked to public microarray data in ArrayExpress. We have mapped developmental stages between the species to be able to compare developmental time phases. We store the largest collection of gene expression patterns available to date in an individual resource, reflecting 16 505 annotated genes. 4DXpress will be an invaluable tool for developmental as well as for computational biologists interested in gene regulation and evolution. 4DXpress is available at http://ani.embl.de/4DXpress.
377.
A Molecular Study of Microbe Transfer between Distant Environments.
Abstract + PDFBACKGROUND: Environments and their organic content are generally not static and isolated, but in a constant state of exchange and interaction with each other. Through physical or biological processes, organisms, especially microbes, may be transferred between environments whose characteristics may be quite different. The transferred microbes may not survive in their new environment, but their DNA will be deposited. In this study, we compare two environmental sequencing projects to find molecular evidence of transfer of microbes over vast geographical distances. METHODOLOGY: By studying synonymous nucleotide composition, oligomer frequency and orthology between predicted genes in metagenomics data from two environments, terrestrial and aquatic, and by correlating with phylogenetic mappings, we find that both environments are likely to contain trace amounts of microbes which have been far removed from their original habitat. We also suggest a bias in direction from soil to sea, which is consistent with the cycles of planetary wind and water. CONCLUSIONS: Our findings support the Baas-Becking hypothesis formulated in 1934, which states that due to dispersion and population sizes, microbes are likely to be found in widely disparate environments. Furthermore, the availability of genetic material from distant environments is a possible font of novel gene functions for lateral gene transfer.
375.
Circular reasoning rather than cyclic expression.
Jensen LJ, de Lichtenberg U, Jensen TS, Brunak S, Bork P
2008 Jun 23; 9(6): 403. Epub 2008 Jun 23; PubMed: 18598377.
Abstract + PDF: A response to Combined analysis reveals a core set of cycling genes by Y Lu, S Mahony, PV Benos, R Rosenfeld, I Simon, LL Breeden and Z Bar-Joseph. Genome Biol 2007, 8:R146.
374.
eggNOG: automated construction and annotation of orthologous groups of genes.
2008 Jan 16; 36: D250-4. Epub 2007 Oct 16; PubMed: 17942413.
Abstract + PDFThe identification of orthologous genes forms the basis for most comparative genomics studies. Existing approaches either lack functional annotation of the identified orthologous groups, hampering the interpretation of subsequent results, or are manually annotated and thus lag behind the rapid sequencing of new genomes. Here we present the eggNOG database ('evolutionary genealogy of genes: Non-supervised Orthologous Groups'), which contains orthologous groups constructed from Smith-Waterman alignments through identification of reciprocal best matches and triangular linkage clustering. Applying this procedure to 312 bacterial, 26 archaeal and 35 eukaryotic genomes yielded 43 582 course-grained orthologous groups of which 9724 are extended versions of those from the original COG/KOG database. We also constructed more fine-grained groups for selected subsets of organisms, such as the 19 914 mammalian orthologous groups. We automatically annotated our non-supervised orthologous groups with functional descriptions, which were derived by identifying common denominators for the genes based on their individual textual descriptions, annotated functional categories, and predicted protein domains. The orthologous groups in eggNOG contain 1 241 751 genes and provide at least a broad functional description for 77% of them. Users can query the resource for individual genes via a web interface or download the complete set of orthologous groups at http://eggnog.embl.de.
373.
The genome of the choanoflagellate Monosiga brevicollis and the origin of metazoans.
King N, Westbrook MJ, Young SL, Kuo A, Abedin M, Chapman J, Fairclough S, Hellsten U, Isogai Y, Letunic I, Marr M, Pincus D, Putnam N, Rokas A, Wright KJ, Zuzow R, Dirks W, Good M, Goodstein D, Lemons D, Li W, Lyons JB, Morris A, Nichols S, Richter DJ, Salamov A, Sequencing JG, Bork P, Lim WA, Manning G, Miller WT, McGinnis W, Shapiro H, Tjian R, Grigoriev IV, Rokhsar D
Abstract + PDFChoanoflagellates are the closest known relatives of metazoans. To discover potential molecular mechanisms underlying the evolution of metazoan multicellularity, we sequenced and analysed the genome of the unicellular choanoflagellate Monosiga brevicollis. The genome contains approximately 9,200 intron-rich genes, including a number that encode cell adhesion and signalling protein domains that are otherwise restricted to metazoans. Here we show that the physical linkages among protein domains often differ between M. brevicollis and metazoans, suggesting that abundant domain shuffling followed the separation of the choanoflagellate and metazoan lineages. The completion of the M. brevicollis genome allows us to reconstruct with increasing resolution the genomic changes that accompanied the origin of metazoans.
372.
Frameshift mutations in coding repeats of protein tyrosine phosphatase genes in colorectal tumors with microsatellite instability.
Korff S, Woerner SM, Yuan YP, Bork P, von Knebel Doeberitz M, Gebert J
2008 Nov 10; 8(1): 329. Epub 2008 Nov 10; PubMed: 19000305.
Abstract + PDFABSTRACT: BACKGROUND: Protein tyrosine phosphatases (PTPs) like their antagonizing protein tyrosine kinases are key regulators of signal transduction thereby assuring normal control of cellular growth and differentiation. Increasing evidence suggests that mutations in PTP genes are associated with human malignancies. For example, mutational analysis of the tyrosine phosphatase (PTP) gene superfamily uncovered genetic alterations in about 26 % of colorectal tumors. Since in these studies tumors have not been stratified according to genetic instability status we hypothesized that colorectal tumors characterized by high-level of microsatellite instability (MSI-H) might show an increased frequency of frameshift mutations in those PTP genes that harbor long mononucleotide repeats in their coding region (cMNR). RESULTS: Using bioinformatic analysis we identified 16 PTP candidate genes with long cMNRs that were examined for genetic alterations in 19 MSI-H colon cell lines, 54 MSI-H colorectal cancers, and 17 MSI-H colorectal adenomas. Frameshift mutations were identified only in 6 PTP genes, of which PTPN21 show the highest mutation frequency at all in MSI-H tumors (17 %). CONCLUSIONS: Although about 32 % of MSI-H tumors showed at least one affected PTP gene, and cMNR mutation rates in PTPN21, PTPRS, and PTPN5 are higher than the mean mutation frequency of MNRs of the same length, mutations within PTP genes do not seem to play a common role in MSI tumorigenesis, since no cMNR mutation frequency reached statistical significance and therefore, failed prediction as a Positive Selective Target Gene.
371.
Large-scale prediction of drug-target relationships.
Abstract + PDFThe rapidly increasing amount of publicly available knowledge in biology and chemistry enables scientists to revisit many open problems by the systematic integration and analysis of heterogeneous novel data. The integration of relevant data does not only allow analyses at the network level, but also provides a more global view on drug-target relations. Here we review recent attempts to apply large-scale computational analyses to predict novel interactions of drugs and targets from molecular and cellular features. In this context, we quantify the family-dependent probability of two proteins to bind the same ligand as function of their sequence similarity. We finally discuss how phenotypic data could help to expand our understanding of the complex mechanisms of drug action.
370.
STITCH: interaction networks of chemicals and proteins.
2008 Jan 15; 36: D684-8. Epub 2007 Dec 15; PubMed: 18084021.
Abstract + PDFThe knowledge about interactions between proteins and small molecules is essential for the understanding of molecular and cellular functions. However, information on such interactions is widely dispersed across numerous databases and the literature. To facilitate access to this data, STITCH ('search tool for interactions of chemicals') integrates information about interactions from metabolic pathways, crystal structures, binding experiments and drug-target relationships. Inferred information from phenotypic effects, text mining and chemical structure similarity is used to predict relations between chemicals. STITCH further allows exploring the network of chemical relations, also in the context of associated binding proteins. Each proposed interaction can be traced back to the original data sources. Our database contains interaction information for over 68 000 different chemicals, including 2200 drugs, and connects them to 1.5 million genes across 373 genomes and their interactions contained in the STRING database. STITCH is available at http://stitch.embl.de/
369.
Millimeter-scale genetic gradients and community-level molecular convergence in a hypersaline microbial mat.
Kunin V, Raes J, Harris JK, Spear JR, Walker JJ, Ivanova N, von Mering C, Bebout BM, Pace NR, Bork P, Hugenholtz P
2008; 4: 198. PubMed: 18523433.
Abstract + PDFTo investigate the extent of genetic stratification in structured microbial communities, we compared the metagenomes of 10 successive layers of a phylogenetically complex hypersaline mat from Guerrero Negro, Mexico. We found pronounced millimeter-scale genetic gradients that were consistent with the physicochemical profile of the mat. Despite these gradients, all layers displayed near-identical and acid-shifted isoelectric point profiles due to a molecular convergence of amino-acid usage, indicating that hypersalinity enforces an overriding selective pressure on the mat community.
368.
iPath: interactive exploration of biochemical pathways and networks.
2008 Mar 12; 33(3): 101-3. Epub 2008 Feb 13; PubMed: 18276143.
Abstract + PDFiPath is an open-access online tool (http://pathways.embl.de) for visualizing and analyzing metabolic pathways. An interactive viewer provides straightforward navigation through various pathways and enables easy access to the underlying chemicals and enzymes. Customized pathway maps can be generated and annotated using various external data. For example, by merging human genome data with two important gut commensals, iPath can pinpoint the complementarity of the host-symbiont metabolic capacities.
367.
NetworKIN: a resource for exploring cellular phosphorylation networks.
Linding R, Jensen LJ, Pasculescu A, Olhovsky M, Colwill K, Bork P, Yaffe MB, Pawson T
2008 Jan 2; 36: D695-9. Epub 2007 Nov 2; PubMed: 17981841.
Abstract + PDFProtein kinases control cellular responses by phosphorylating specific substrates. Recent proteome-wide mapping of protein phosphorylation sites by mass spectrometry has discovered thousands of in vivo sites. Systematically assigning all 518 human kinases to all these sites is a challenging problem. The NetworKIN database (http://networkin.info) integrates consensus substrate motifs with context modelling for improved prediction of cellular kinase-substrate relations. Based on the latest human phosphoproteome from the Phospho.ELM and PhosphoSite databases, the resource offers insight into phosphorylation-modulated interaction networks. Here, we describe how NetworKIN can be used for both global and targeted molecular studies. Via the web interface users can query the database of precomputed kinase-substrate relations or obtain predictions on novel phosphoproteins. The database currently contains a predicted phosphorylation network with 20 224 site-specific interactions involving 3978 phosphoproteins and 73 human kinases from 20 families.
366.
Linear motif atlas for phosphorylation-dependent signaling.
Miller ML, Jensen LJ, Diella F, Jørgensen C, Tinti M, Li L, Hsiung M, Parker SA, Bordeaux J, Sicheritz-Ponten T, Olhovsky M, Pasculescu A, Alexander J, Knapp S, Blom N, Bork P, Li S, Cesareni G, Pawson T, Turk BE, Yaffe MB, Brunak S, Linding R
2008 Sep 2; 1(35): ra2. PubMed: 18765831.
Abstract + PDFSystematic and quantitative analysis of protein phosphorylation is revealing dynamic regulatory networks underlying cellular responses to environmental cues. However, matching these sites to the kinases that phosphorylate them and the phosphorylation-dependent binding domains that may subsequently bind to them remains a challenge. NetPhorest is an atlas of consensus sequence motifs that covers 179 kinases and 104 phosphorylation-dependent binding domains [Src homology 2 (SH2), phosphotyrosine binding (PTB), BRCA1 C-terminal (BRCT), WW, and 14-3-3]. The atlas reveals new aspects of signaling systems, including the observation that tyrosine kinases mutated in cancer have lower specificity than their non-oncogenic relatives. The resource is maintained by an automated pipeline, which uses phylogenetic trees to structure the currently available in vivo and in vitro data to derive probabilistic sequence models of linear motifs. The atlas is available as a community resource (http://netphorest.info).
365.
KEGG Atlas mapping for global analysis of metabolic pathways.
Okuda S, Yamada T, Hamajima M, Itoh M, Katayama T, Bork P, Goto S, Kanehisa M
2008 Jul 1; 36: W423-6. Epub 2008 May 13; PubMed: 18477636.
Abstract + PDFKEGG Atlas is a new graphical interface to the KEGG suite of databases, especially to the systems information in the PATHWAY and BRITE databases. It currently consists of a single global map and an associated viewer for metabolism, covering about 120 KEGG metabolic pathway maps and about 10 BRITE hierarchies. The viewer allows the user to navigate and zoom the global map under the Ajax technology. The mapping of high-throughput experimental data onto the global map is the main use of KEGG Atlas. In the global metabolism map, the node (circle) is a chemical compound and the edge (line) is a set of reactions linked to a set of KEGG Orthology (KO) entries for enzyme genes. Once gene identifiers in different organisms are converted to the K number identifiers in the KO system, corresponding line segments can be highlighted in the global map, allowing the user to view genome sequence data as organism-specific pathways, gene expression data as up- or down-regulated pathways, etc. Once chemical compounds are converted to the C number identifiers in KEGG, metabolomics data can also be displayed in the global map. KEGG Atlas is available at http://www.genome.jp/kegg/atlas/.
364.
Large gene overlaps in prokaryotic genomes: result of functional constraints or mispredictions?
Palleja A, Harrington ED, Bork P
2008 Jul 15; 9(1): 335. Epub 2008 Jul 15; PubMed: 18627618.
Abstract + PDFABSTRACT: BACKGROUND: Across the fully sequenced microbial genomes there are thousands of examples of overlapping genes. Many of these are only a few nucleotides long and are thought to function by permitting the coordinated regulation of gene expression. However, there should also be selective pressure against long overlaps, as the existence of overlapping reading frames increases the risk of deleterious mutations. Here we examine the longest overlaps and assess whether they are the product of special functional constraints or of erroneous annotation. RESULTS: We analysed the genes that overlap by 60 bps or more among 338 fully-sequenced prokaryotic genomes. The likely functional significance of an overlap was determined by comparing each of the genes to its respective orthologs. If a gene showed a significantly different length from its orthologs it was considered unlikely to be functional and therefore the result of an error either in sequencing or gene prediction. Focusing on 715 co-directional overlaps longer than 60 bps, we classified the erroneous ones into five categories: i) 5'-end extension of the downstream gene due to either a mispredicted start codon or a frameshift at 5'-end of the gene (409 overlaps), ii) fragmentation of a gene caused by a frameshift (163), iii) 3'-end extension of the upstream gene due to either a frameshift at 3'-end of a gene or point mutation at the stop codon (68), iv) Redundant gene predictions (4), v) 5' & 3'-end extension which is a combination of i) and iii) (71). We also studied 75 divergent overlaps that could be classified as misannotations of group i). Nevertheless we found some convergent long overlaps (54) that might be true overlaps, although an important part of convergent overlaps could be classified as group iii) (124). CONCLUSIONS: Among the 968 overlaps larger than 60 bps which we analysed, we did not find a single real one among the co-directional and divergent orientations and concluded that there had been an excessive number of misannotations. Only convergent orientation seems to permit some long overlaps, although convergent overlaps are also hampered by misannotations. We propose a simple rule to flag these erroneous gene length predictions to facilitate automatic annotation.
363.
Heat shock protein-90-alpha, a prolactin-STAT5 target gene identified in breast cancer cells, is involved in apoptosis regulation.
Perotti C, Liu R, Parusel C, Boecher N, Schultz J, Bork P, Pfitzner E, Groner B, Shemanko C
2008 Nov 13; 10(6): R94. Epub 2008 Nov 13; PubMed: 19014541.
Abstract + PDFABSTRACT: INTRODUCTION: The prolactin-Janus-kinase-2-signal transducer and activator of transcription-5 (JAK2-STAT5) pathway is essential for the development and the functional differentiation of the mammary gland. The pathway also has important roles in mammary tumourigenesis. Prolactin regulated target genes are not yet well defined in tumour cells, and we undertook the first large genetic screen of breast cancer cells treated with or without exogenous prolactin. We hypothesize that the identification of these genes should yield insights into the mechanisms by which prolactin participates in cancer formation or progression and possibly how it also regulates normal mammary gland development. METHODS: We used subtractive hybridization to identify a number of prolactin-regulated genes in the human mammary carcinoma cell line SKBR3. Northern analysis and luciferase assays identified the gene encoding heat shock protein 90-alpha (HSP90A) as a prolactin-JAK2-STAT5 target gene, whose function was characterized using apoptosis assays. RESULTS: We identified a number of new prolactin-regulated genes in breast cancer cells. Focusing on HSP90A, we determined that prolactin increased HSP90A mRNA in cancerous human breast SKBR3 cells and that STAT5B preferentially activated the HSP90A promoter in reporter gene assays. Both prolactin and its downstream protein effector, HSP90-alpha, promote survival, as shown by apoptosis assays and by the addition of the heat shock protein 90 inhibitor, 17-allylamino-17-demethoxygeldanamycin (17-AAG), in both untransformed HC11 mammary epithelial cells and SKBR3 breast cancer cells. The constitutive expression of HSP90A, however, sensitized differentiated HC11 cells to starvation-induced wild-type p53-independent apoptosis. Interestingly, in SKBR3 breast cancer cells, HSP90-alpha promoted survival in the presence of serum but appeared to have little effect during starvation. CONCLUSIONS: In addition to identifying new prolactin regulated genes in breast cancer cells, we found that prolactin-JAK2-STAT5 induces expression of the HSP90A gene, which encodes the master chaperone of cancer. This identifies one mechanism by which prolactin contributes to breast cancer. Increased HSP90-alpha expression in breast cancer is correlated with increased cell survival and poor prognosis and HSP90-alpha inhibitors are being tested in clinical trials as a breast cancer treatment. Our results also indicate that HSP90-alpha promotes survival depending upon the cellular conditions and state of cellular transformation.
362.
Evolution of the phospho-tyrosine signaling machinery in premetazoan lineages.
Pincus D, Letunic I, Bork P, Lim WA
2008 Jul 15; 105(28): 9680-4. Epub 2008 Jul 3; PubMed: 18599463. Media echos.
Abstract + PDFMulticellular animals use a three-part molecular toolkit to mediate phospho-tyrosine signaling: Tyrosine kinases (TyrK), protein tyrosine phosphatases (PTP), and Src Homology 2 (SH2) domains function, respectively, as "writers," "erasers," and "readers" of phospho-tyrosine modifications. How did this system of three components evolve, given their interdependent function? Here, we examine the usage of these components in 41 eukaryotic genomes, including the newly sequenced genome of the choanoflagellate, Monosiga brevicollis, the closest known unicellular relative to metazoans. This analysis indicates that SH2 and PTP domains likely evolved earliest-a handful of these domains are found in premetazoan eukaryotes lacking tyrosine kinases, most likely to deal with limited tyrosine phosphorylation cross-catalyzed by promiscuous Ser/Thr kinases. Modern TyrK proteins, however, are only observed in two lineages, metazoans and choanoflagellates. These two lineages show a dramatic coexpansion of all three domain families. Concurrent expansion of the three domain families is consistent with a stepwise evolutionary model in which preexisting SH2 and PTP domains were of limited utility until the appearance of the TyrK domain in the last common ancestor of metazoans and choanoflagellates. The emergence of the full three-component signaling system, with its dramatically increased encoding potential, may have contributed to the advent of metazoan multicellularity.
361.
Selective maintenance of Drosophila tandemly-arranged duplicated genes during evolution.
2008 Dec 16; 9(12): R176. Epub 2008 Dec 16; PubMed: 19087263.
Abstract + PDFABSTRACT: BACKGROUND: The physical organization and chromosomal localization of genes within genomes is known to play an important role in their function. Most genes arise by duplication and move along the genome by random shuffling of DNA segments. Higher order structuring of the genome occurs in eukaryotes, where groups of physically linked genes are co-expressed. However, the contribution of gene duplication to gene order has been not analyzed in detail, as it is believed that co-expression due to recent duplicates would obscure other domains of co-expression. RESULTS: We have catalogued ordered duplicated genes in Drosophila melanogaster, and found that one in five of all genes are organized as tandem arrays. Furthermore, among arrays that have been spatially conserved over longer periods than would be expected on the basis of random shuffling, a disproportionate number contain genes encoding developmental regulators. Using in-situ gene expression data for more than half of the Drosophila genome, we find that genes in these conserved clusters are co-expressed to a much higher extent than other duplicated genes. CONCLUSIONS: These results reveal the existence of functional constraints in insects that retain copies of genes encoding developmental and regulatory proteins as neighbours, allowing their co-expression. This co-expression may be the result of shared cis regulatory elements or a shared need for a specific chromatin structure. Our results highlight the association between genome architecture and the gene regulatory networks involved in the construction of the body plan.
360.
Molecular eco-systems biology: towards an understanding of community function.
Raes J, Bork P
2008 Sep 30; 6(9): 693-9. Epub 2008 Jun 30; PubMed: 18587409.
Abstract + PDFSystems-biology approaches, which are driven by genome sequencing and high-throughput functional genomics data, are revolutionizing single-cell-organism biology. With the advent of various high-throughput techniques that aim to characterize complete microbial ecosystems (metagenomics, meta-transcriptomics and meta-metabolomics), we propose that the time is ripe to consider molecular systems biology at the ecosystem level (eco-systems biology). Here, we discuss the necessary data types that are required to unite molecular microbiology and ecology to develop an understanding of community function and discuss the potential shortcomings of these approaches.
359.
Enhanced function annotations for Drosophila serine proteases: A case study for systematic annotation of multi-member gene families.
Shah PK, Tripathi LP, Jensen LJ, Gahnim M, Mason C, Furlong EE, Rodrigues V, White KP, Bork P, Sowdhamini R
Abstract + PDFSystematically annotating function of enzymes that belong to large protein families encoded in a single eukaryotic genome is a very challenging task. We carried out such an exercise to annotate function for serine-protease family of the trypsin fold in Drosophila melanogaster, with an emphasis on annotating serine-protease homologues (SPHs) that may have lost their catalytic function. Our approach involves data mining and data integration to provide function annotations for 190 Drosophila gene products containing serine-protease-like domains, of which 35 are SPHs. This was accomplished by analysis of structure-function relationships, gene-expression profiles, large-scale protein-protein interaction data, literature mining and bioinformatic tools. We introduce functional residue clustering (FRC), a method that performs hierarchical clustering of sequences using properties of functionally important residues and utilizes correlation co-efficient as a quantitative similarity measure to transfer in vivo substrate specificities to proteases. We show that the efficiency of transfer of substrate-specificity information using this method is generally high. FRC was also applied on Drosophila proteases to assign putative competitive inhibitor relationships (CIRs). Microarray gene-expression data were utilized to uncover a large-scale and dual involvement of proteases in development and in immune response. We found specific recruitment of SPHs and proteases with CLIP domains in immune response, suggesting evolution of a new function for SPHs. We also suggest existence of separate downstream protease cascades for immune response against bacterial/fungal infections and parasite/parasitoid infections. We verify quality of our annotations using information from RNAi screens and other evidence types. Utilization of such multi-fold approaches results in 10-fold increase of function annotation for Drosophila serine proteases and demonstrates value in increasing annotations in multiple genomes.
358.
Non-random retention of protein-coding overlapping genes in Metazoa.
2008 Apr 16; 9(1): 174. Epub 2008 Apr 16; PubMed: 18416813.
Abstract + PDFABSTRACT: BACKGROUND: Although the overlap of transcriptional units occurs frequently in eukaryotic genomes, its evolutionary and biological significance remains largely unclear. Here we report a comparative analysis of overlaps between genes coding for well-annotated proteins in five metazoan genomes (human, mouse, zebrafish, fruit fly and worm). RESULTS: For all analyzed species the observed number of overlapping genes is always lower than expected assuming functional neutrality, suggesting that gene overlap is negatively selected. The comparison to the random distribution also shows that retained overlaps do not exhibit random features: antiparallel overlaps are significantly enriched, while overlaps lying on the same strand and those involving coding sequences are highly underrepresented. We confirm that overlap is mostly species-specific and provide evidence that it frequently originates through the acquisition of terminal, non-coding exons. Finally, we show that overlapping genes tend to be significantly co-expressed in a breast cancer cDNA library obtained by 454 deep sequencing, and that different overlap types display different patterns of reciprocal expression. CONCLUSIONS: Our data suggest that overlap between protein-coding genes is selected against in Metazoa. However, when retained it may be used as a species-specific mechanism for the reciprocal regulation of neighboring genes. The tendency of overlaps to involve non-coding regions of the genes leads to the speculation that the advantages achieved by an overlapping arrangement may be optimized by evolving regulatory non-coding transcripts.
357.
The genome of the model beetle and pest Tribolium castaneum.
Tribolium Genome Sequencing Consortium , Project leader , Richards S, Principal investigators , Gibbs RA, Weinstock GM, White paper , Brown SJ, Denell R, Beeman RW, Gibbs R, Analysis leaders , Beeman RW, Brown SJ, Bucher G, Friedrich M, Grimmelikhuijzen CJ, Klingler M, Lorenzen M, Richards S, Roth S, Schröder R, Tautz D, Zdobnov EM, DNA sequence and global analysis: DNA sequencing , Muzny D, Gibbs RA, Weinstock GM, Attaway T, Bell S, Buhay CJ, Chandrabose MN, Chavez D, Clerk-Blankenburg KP, Cree A, Dao M, Davis C, Chacko J, Dinh H, Dugan-Rocha S, Fowler G, Garner TT, Garnes J, Gnirke A, Hawes A, Hernandez J, Hines S, Holder M, Hume J, Jhangiani SN, Joshi V, Khan ZM, Jackson L, Kovar C, Kowis A, Lee S, Lewis LR, Margolis J, Morgan M, Nazareth LV, Nguyen N, Okwuonu G, Parker D, Richards S, Ruiz SJ, Santibanez J, Savard J, Scherer SE, Schneider B, Sodergren E, Tautz D, Vattahil S, Villasana D, White CS, Wright R, EST sequencing , Park Y, Beeman RW, Lord J, Oppert B, Lorenzen M, Brown S, Wang L, Savard J, Tautz D, Richards S, Weinstock G, Gibbs RA, genome assembly , Liu Y, Worley K, Weinstock G, G+C content , Elsik CG, Reese JT, Elhaik E, Landan G, Graur D, repetitive DNA, transposons and telomeres , Arensburger P, Atkinson P, Beeman RW, Beidler J, Brown SJ, Demuth JP, Drury DW, Du YZ, Fujiwara H, Lorenzen M, Maselli V, Osanai M, Park Y, Robertson HM, Tu Z, Wang JJ, Wang S, gene prediction and consensus gene set , Richards S, Song H, Zhang L, Sodergren E, Werner D, Stanke M, Morgenstern B, Solovyev V, Kosarev P, Brown G, Chen HC, Ermolaeva O, Hlavina W, Kapustin Y, Kiryutin B, Kitts P, Maglott D, Pruitt K, Sapojnikov V, Souvorov A, Mackey AJ, Waterhouse RM, Wyder S, Zdobnov EM, global gene content analysis , Zdobnov EM, Wyder S, Kriventseva EV, Kadowaki T, Bork P, Developmental processes and signalling pathways , Aranda M, Bao R, Beermann A, Berns N, Bolognesi R, Bonneton F, Bopp D, Brown SJ, Bucher G, Butts T, Chaumot A, Denell RE, Ferrier DE, Friedrich M, Gordon CM, Jindra M, Klingler M, Lan Q, Lattorff HM, Laudet V, von Levetsow C, Liu Z, Lutz R, Lynch JA, da Fonseca RN, Posnien N, Reuter R, Roth S, Savard J, Schinko JB, Schmitt C, Schoppmeier M, Schröder R, Shippy TD, Simonnet F, Marques-Souza H, Tautz D, Tomoyasu Y, Trauner J, Van der Zee M, Vervoort M, Wittkopp N, Wimmer EA, Yang X, Pest biology, senses, Medea and RNAi: ligand gated ion channels , Jones AK, Sattelle DB, oxidative phosphorylation , Ebert PR, P450 genes , Nelson D, Scott JG, Beeman RW, chitin and cuticular proteins , Muthukrishnan S, Kramer KJ, Arakane Y, Beeman RW, Zhu Q, Hogenkamp D, Dixit R, digestive proteinases , Oppert B, Jiang H, Zou Z, Marshall J, Elpidina E, Vinokurov K, Oppert C, immunity , Zou Z, Evans J, Lu Z, Zhao P, Sumathipala N, Altincicek B, Vilcinskas A, Williams M, Hultmark D, Hetru C, Jiang H, neurohormones and GPCRs , Grimmelikhuijzen CJ, Hauser F, Cazzamali G, Williamson M, Park Y, Li B, Tanaka Y, Predel R, Neupert S, Schachtner J, Verleyen P, neuropeptide processing enzymes , Raible F, Bork P, opsins , Friedrich M, odorant receptors and gustatory receptors , Walden KK, Robertson HM, odorant binding and chemosensory proteins , Angeli S, Forêt S, Bucher G, Schuetz S, Maleszka R, Wimmer EA, Medea , Beeman RW, Lorenzen M, systemic RNAi , Tomoyasu Y, Miller SC, Grossmann D, Bucher G
Abstract + PDFTribolium castaneum is a member of the most species-rich eukaryotic order, a powerful model organism for the study of generalized insect development, and an important pest of stored agricultural products. We describe its genome sequence here. This omnivorous beetle has evolved the ability to interact with a diverse chemical environment, as shown by large expansions in odorant and gustatory receptors, as well as P450 and other detoxification enzymes. Development in Tribolium is more representative of other insects than is Drosophila, a fact reflected in gene content and function. For example, Tribolium has retained more ancestral genes involved in cell-cell communication than Drosophila, some being expressed in the growth zone crucial for axial elongation in short-germ development. Systemic RNA interference in T. castaneum functions differently from that in Caenorhabditis elegans, but nevertheless offers similar power for the elucidation of gene function and identification of targets for selective insect control.
2007 18 publication(s).
356.
Sequence-based factors influencing the expression of heterologous genes in the yeast Pichia pastoris-A comparative view on 79 human genes.
Boettner M, Steffens C, von Mering C, Bork P, Stahl U, Lang C
2007 May 31; 130(1): 1-10. Epub 2007 Feb 28; PubMed: 17389146.
Abstract + PDFHigh yield expression of heterologous proteins is usually a matter of "trial and error". In the search of parameters with a major impact on expression, we have applied a comparative analysis to 79 different human cDNAs expressed in Pichia pastoris. The cDNAs were cloned in an expression vector for intracellular expression and recombinant protein expression was monitored in a standardized procedure and classified with respect to the expression level. Of all sequence-based parameters with a possible influence on the expression level, more than 10 were analysed. Three of those factors proved to have a statistically significant association with the expression level. Low abundance of AT-rich regions in the cDNA associates with a high expression level. A comparatively high isoelectric point of the recombinant protein associates with failure of expression and, finally, the occurrence of a protein homologue in yeast is associated with detectable protein expression. Interestingly, some often discussed factors like codon usage or GC content did not show a significant impact on protein yield. These results could provide a basis for a knowledge-oriented optimisation of gene sequences both to increase protein yields and to help target selection and the design of high-throughput expression approaches.
355.
Splicing factors stimulate polyadenylation via USEs at non-canonical 3' end formation signals.
Danckwardt S, Kaufmann I, Gentzel M, Foerstner KU, Gantzert AS, Gehring NH, Neu-Yilik G, Bork P, Keller W, Wilm M, Hentze MW, Kulozik AE
Abstract + PDFThe prothrombin (F2) 3' end formation signal is highly susceptible to thrombophilia-associated gain-of-function mutations. In its unusual architecture, the F2 3' UTR contains an upstream sequence element (USE) that compensates for weak activities of the non-canonical cleavage site and the downstream U-rich element. Here, we address the mechanism of USE function. We show that the F2 USE contains a highly conserved nonameric core sequence, which promotes 3' end formation in a position- and sequence-dependent manner. We identify proteins that specifically interact with the USE, and demonstrate their function as trans-acting factors that promote 3' end formation. Interestingly, these include the splicing factors U2AF35, U2AF65 and hnRNPI. We show that these splicing factors not only modulate 3' end formation via the USEs contained in the F2 and the complement C2 mRNAs, but also in the biocomputationally identified BCL2L2, IVNS and ACTR mRNAs, suggesting a broader functional role. These data uncover a novel mechanism that functionally links the splicing and 3' end formation machineries of multiple cellular mRNAs in an USE-dependent manner.
354.
Target-specific requirements for enhancers of decapping in miRNA-mediated gene silencing.
Eulalio A, Rehwinkel J, Stricker M, Huntzinger E, Yang SF, Doerks T, Dorner S, Bork P, Boutros M, Izaurralde E
Abstract + PDFmicroRNAs (miRNAs) silence gene expression by suppressing protein production and/or by promoting mRNA decay. To elucidate how silencing is accomplished, we screened an RNA interference library for suppressors of miRNA-mediated regulation in Drosophila melanogaster cells. In addition to proteins known to be required for miRNA biogenesis and function (i.e., Drosha, Pasha, Dicer-1, AGO1, and GW182), the screen identified the decapping activator Ge-1 as being required for silencing by miRNAs. Depleting Ge-1 alone and/or in combination with other decapping activators (e.g., DCP1, EDC3, HPat, or Me31B) suppresses silencing of several miRNA targets, indicating that miRNAs elicit mRNA decapping. A comparison of gene expression profiles in cells depleted of AGO1 or of individual decapping activators shows that approximately 15% of AGO1-targets are also regulated by Ge-1, DCP1, and HPat, whereas 5% are dependent on EDC3 and LSm1-7. These percentages are underestimated because decapping activators are partially redundant. Furthermore, in the absence of active translation, some miRNA targets are stabilized, whereas others continue to be degraded in a miRNA-dependent manner. These findings suggest that miRNAs mediate post-transcriptional gene silencing by more than one mechanism.
353.
Quantitative assessment of protein function prediction from metagenomics shotgun sequences.
2007 Aug 28; 104(35): 13913-8. Epub 2007 Aug 23; PubMed: 17717083.
Abstract + PDFTo assess the potential of protein function prediction in environmental genomics data, we analyzed shotgun sequences from four diverse and complex habitats. Using homology searches as well as customized gene neighborhood methods that incorporate intergenic and evolutionary distances, we inferred specific functions for 76% of the 1.4 million predicted ORFs in these samples (83% when nonspecific functions are considered). Surprisingly, these fractions are only slightly smaller than the corresponding ones in completely sequenced genomes (83% and 86%, respectively, by using the same methodology) and considerably higher than previously thought. For as many as 75,448 ORFs (5% of the total), only neighborhood methods can assign functions, illustrated here by a previously undescribed gene associated with the well characterized heme biosynthesis operon and a potential transcription factor that might regulate a coupling between fatty acid biosynthesis and degradation. Our results further suggest that, although functions can be inferred for most proteins on earth, many functions remain to be discovered in numerous small, rare protein families.
352.
Identification of tightly regulated groups of genes during Drosophila melanogaster embryogenesis.
2007; 3: 72. PubMed: 17224916.
Abstract + PDFTime-series analysis of whole-genome expression data during Drosophila melanogaster development indicates that up to 86% of its genes change their relative transcript level during embryogenesis. By applying conservative filtering criteria and requiring 'sharp' transcript changes, we identified 1534 maternal genes, 792 transient zygotic genes, and 1053 genes whose transcript levels increase during embryogenesis. Each of these three categories is dominated by groups of genes where all transcript levels increase and/or decrease at similar times, suggesting a common mode of regulation. For example, 34% of the transiently expressed genes fall into three groups, with increased transcript levels between 2.5-12, 11-20, and 15-20 h of development, respectively. We highlight common and distinctive functional features of these expression groups and identify a coupling between downregulation of transcript levels and targeted protein degradation. By mapping the groups to the protein network, we also predict and experimentally confirm new functional associations.
351.
Interactive Tree Of Life (iTOL): an online tool for phylogenetic tree display and annotation.
Letunic I, Bork P
2007 Jan 1; 23(1): 127-8. Epub 2006 Oct 18; PubMed: 17050570.
Abstract + PDFSUMMARY: Interactive Tree Of Life (iTOL) is a web based tool for the display, manipulation and annotation of phylogenetic trees. Trees can be interactively pruned and re-rooted. Various types of data such as genome sizes or protein domain repertoires can be mapped onto the tree. Export to several bitmap and vector graphics formats is supported. AVAILABILITY: iTOL is available through WWW at http://itol.embl.de.
350.
Evolution of Cell Cycle Control: Same Molecular Machines, Different Regulation.
Lichtenberg UD, Jensen TS, Brunak S, Bork P, Jensen LJ
2007 Aug 1; 6(15): 1819-25. Epub 2007 Jun 4; PubMed: 17671420.
Abstract + PDFDecades of research has together with the availability of whole genomes made it clear that many of the core components involved in the cell cycle are conserved acrosseukaryotes, both functionally and structurally. These proteins are organized in complexes and modules that are activated or deactivated at specific stages during the cell cycle through a wide variety of mechanisms including transcriptional regulation, phosphorylation, subcellular translocation and targeted degradation. In a series of integrative analyses of different genome-scale data sets, we have studied how these different layers of regulation together control the activity of cell cycle complexes and how this regulation has evolved. The results show surprisingly poor conservation of both the transcriptional and the post-translation regulation of individual genes and proteins; however, the changes in one layer of regulation are often mirrored by changes in other layers, implying that independent layers of control coevolve. By taking a bird's eye view of the cell cycle, we demonstrate how the modular organization of cellular systems possesses a built-in flexibility, which allows evolution to find many different solutions for assembling the same molecular machines just in time for action.
349.
Systematic Discovery of In Vivo Phosphorylation Networks.
Linding R, Jensen LJ, Ostheimer GJ, van Vugt MA, Jørgensen C, Miron IM, Diella F, Colwill K, Taylor L, Elder K, Metalnikov P, Nguyen V, Pasculescu A, Jin J, Park JG, Samson LD, Woodgett JR, Russell RB, Bork P, Yaffe MB, Pawson T
Abstract + PDFProtein kinases control cellular decision processes by phosphorylating specific substrates. Thousands of in vivo phosphorylation sites have been identified, mostly by proteome-wide mapping. However, systematically matching these sites to specific kinases is presently infeasible, due to limited specificity of consensus motifs, and the influence of contextual factors, such as protein scaffolds, localization, and expression, on cellular substrate specificity. We have developed an approach (NetworKIN) that augments motif-based predictions with the network context of kinases and phosphoproteins. The latter provides 60%-80% of the computational capability to assign in vivo substrate specificity. NetworKIN pinpoints kinases responsible for specific phosphorylations and yields a 2.5-fold improvement in the accuracy with which phosphorylation networks can be constructed. Applying this approach to DNA damage signaling, we show that 53BP1 and Rad50 are phosphorylated by CDK1 and ATM, respectively. We describe a scalable strategy to evaluate predictions, which suggests that BCLAF1 is a GSK-3 substrate.
348.
New developments in the InterPro database.
Mulder NJ, Apweiler R, Attwood TK, Bairoch A, Bateman A, Binns D, Bork P, Buillard V, Cerutti L, Copley R, Courcelle E, Das U, Daugherty L, Dibley M, Finn R, Fleischmann W, Gough J, Haft D, Hulo N, Hunter S, Kahn D, Kanapin A, Kejariwal A, Labarga A, Langendijk-Genevaux PS, Lonsdale D, Lopez R, Letunic I, Madera M, Maslen J, McAnulla C, McDowall J, Mistry J, Mitchell A, Nikolskaya AN, Orchard S, Orengo C, Petryszak R, Selengut JD, Sigrist CJ, Thomas PD, Valentin F, Wilson D, Wu CH, Yeats C
2007 Jan; 35(Database issue): D224-8. PubMed: 17202162.
Abstract + PDFInterPro is an integrated resource for protein families, domains and functional sites, which integrates the following protein signature databases: PROSITE, PRINTS, ProDom, Pfam, SMART, TIGRFAMs, PIRSF, SUPERFAMILY, Gene3D and PANTHER. The latter two new member databases have been integrated since the last publication in this journal. There have been several new developments in InterPro, including an additional reading field, new database links, extensions to the web interface and additional match XML files. InterPro has always provided matches to UniProtKB proteins on the website and in the match XML file on the FTP site. Additional matches to proteins in UniParc (UniProt archive) are now available for download in the new match XML files only. The latest InterPro release (13.0) contains more than 13 000 entries, covering over 78% of all proteins in UniProtKB. The database is available for text- and sequence-based searches via a webserver (http://www.ebi.ac.uk/interpro), and for download by anonymous FTP (ftp://ftp.ebi.ac.uk/pub/databases/interpro). The InterProScan search tool is now also available via a web service at http://www.ebi.ac.uk/Tools/webservices/WSInterProScan.html.
347.
Use of pathway analysis and genome context methods for functional genomics of Mycoplasma pneumoniae nucleotide metabolism.
Abstract + PDFElementary modes analysis allows one to reveal whether a set of known enzymes is sufficient to sustain functionality of the cell. Moreover, it is helpful in detecting missing reactions and predicting which enzymes could fill these gaps. Here, we perform a comprehensive elementary modes analysis and a genomic context analysis of Mycoplasma pneumoniae nucleotide metabolism, and search for new enzyme activities. The purine and pyrimidine networks are reconstructed by assembling enzymes annotated in the genome or found experimentally. We show that these reaction sets are sufficient for enabling synthesis of DNA and RNA in M. pneumoniae. Special focus is on the key modes for growth. Moreover, we make an educated guess on the nutritional requirements of this micro-organism. For the case that M. pneumoniae does not require adenine as a substrate, we suggest adenylosuccinate synthetase (EC 6.3.4.4), adenylosuccinate lyase (EC 4.3.2.2) and GMP reductase (EC 1.7.1.7) to be operative. GMP reductase activity is putatively assigned to the NRDI_MYCPN gene on the basis of the genomic context analysis. For the pyrimidine network, we suggest CTP synthase (EC 6.3.4.2) to be active. Further experiments on the nutritional requirements are needed to make a decision. Pyrimidine metabolism appears to be more appropriate as a drug target than purine metabolism since it shows lower plasticity.
346.
Update of the G2D tool for prioritization of gene candidates to inherited diseases.
Perez-Iratxeta C, Bork P, Andrade-Navarro MA
2007 Jul 1; 35: W212-6. Epub 2007 May 3; PubMed: 17478516.
Abstract + PDFG2D (genes to diseases) is a web resource for prioritizing genes as candidates for inherited diseases. It uses three algorithms based on different prioritization strategies. The input to the server is the genomic region where the user is looking for the disease-causing mutation, plus an additional piece of information depending on the algorithm used. This information can either be the disease phenotype (described as an online Mendelian inheritance in man (OMIM) identifier), one or several genes known or suspected to be associated with the disease (defined by their Entrez Gene identifiers), or a second genomic region that has been linked as well to the disease. In the latter case, the tool uses known or predicted interactions between genes in the two regions extracted from the STRING database. The output in every case is an ordered list of candidate genes in the region of interest. For the first two of the three methods, the candidate genes are first retrieved through sequence homology search, then scored accordingly to the corresponding method. This means that some of them will correspond to well-known characterized genes, and others will overlap with predicted genes, thus providing a wider analysis. G2D is publicly available at http://www.ogic.ca/projects/g2d_2/
345.
Get the most out of your metagenome: computational analysis of environmental sequence data.
2007 Oct 11; 10(5): 490-8. Epub 2007 Oct 23; PubMed: 17936679.
Abstract + PDFNew advances in sequencing technologies bring random shotgun sequencing of ecosystems within reach of smaller labs, but the complexity of metagenomics data can be overwhelming. Recently, many novel computational tools have been developed to unravel ecosystem properties starting from fragmented sequences. In addition, the so-called 'comparative metagenomics' approaches have allowed the discovery of specific genomic and community adaptations to environmental factors. However, many of the parameters extracted from these data to describe the environment at hand (e.g. genomic features, functional complement, phylogenetic composition) are interdependent and influenced by technical aspects of sample preparation and data treatment, leading to various pitfalls during analysis. To avoid this and complement existing initiatives in data standards, we propose a minimal standard for metagenomics data analysis ('MINIMESS') to be able to take full advantage of the power of comparative metagenomics in understanding microbial life on earth.
344.
Protein function space: viewing the limits or limited by our view?
2007 Jun 14; 17(3): 362-9. Epub 2007 Jun 15; PubMed: 17574832.
Abstract + PDFGiven that the number of protein functions on earth is finite, the rapid expansion of biological knowledge and the concomitant exponential increase in the number of protein sequences should, at some point, enable the estimation of the limits of protein function space. The functional coverage of protein sequences can be investigated using computational methods, especially given the massive amount of data being generated by large-scale environmental sequencing (metagenomics). In completely sequenced genomes, the fraction of proteins to which at least some functional features can be assigned has recently risen to as much as approximately 85%. Although this fraction is more uncertain in metagenomics surveys, because of environmental complexities and differences in analysis protocols, our global knowledge of protein functions still appears to be considerable. However, when we consider protein families, continued sequencing seems to yield an ever-increasing number of novel families. Until we reconcile these two views, the limits of protein space will remain obscured.
343.
Prediction of effective genome size in metagenomic samples.
2007 Jan 15; 8(1): R10. Epub 2007 Jan 15; PubMed: 17224063.
Abstract + PDFABSTRACT: We introduce a novel computational approach to predict effective genome size (EGS - a measure that includes multiple plasmid copies, inserted sequences and associated phages and viruses) from short sequencing reads of environmental genomics (or metagenomics) projects. We observe considerable EGS differences between environments and link this with ecological complexity as well as species composition (i.e. eukaryotes). For example, we estimate EGS in a complex, organism-dense farm soil sample at about 6.3 Mb whereas that of the bacteria therein is only 4.7 Mb; for bacteria in a nutrient-poor, organism-sparse ocean surface water sample, EGS is as low as 1.6 Mb. The method also permits evaluation of completion status and assembly bias in single-genome sequencing projects.
342.
Genome-Wide Experimental Determination of Barriers to Horizontal Gene Transfer.
Sorek R, Zhu Y, Creevey CJ, Francino MP, Bork P, Rubin EM
Abstract + PDFHorizontal gene transfer, in which genetic material is transferred from the genome of one organism to another, has been investigated in microbial species mainly through computational sequence analyses. To address the lack of experimental data, we studied the attempted movement of 246,045 genes from 79 prokaryotic genomes into Escherichia coli and identified genes that consistently fail to transfer. We studied the mechanisms underlying transfer inhibition by placing coding regions from different species under the control of inducible promoters. Our data suggest that toxicity to the host inhibited transfer regardless of the species of origin and that increased gene dosage and associated increased expression may be a predominant cause for transfer failure. While these experimental studies examined transfer solely into E. coli, a computational analysis of gene transfer rates across available bacterial and archaeal genomes supports that the barriers observed in our study are general across the tree of life.
341.
Quantitative Phylogenetic Assessment of Microbial Communities in Diverse Environments.
Abstract + PDFThe taxonomic composition of environmental communities is an important indicator of their ecology and function. Here, we use a set of protein-coding marker genes, extracted from large-scale environmental shotgun sequencing data, to provide a more direct, quantitative and accurate picture of community composition than traditional rRNA-based approaches using polymerase chain reaction (PCR). By mapping marker genes from four diverse environmental data sets onto a reference species phylogeny, we show that certain communities evolve faster than others, determine preferred habitats for entire microbial clades, and provide evidence that such habitat preferences are often remarkably stable over time.
340.
STRING 7--recent developments in the integration and prediction of protein interactions.
2007 Jan 10; 35: D358-62. Epub 2006 Nov 10; PubMed: 17098935.
Abstract + PDFInformation on protein-protein interactions is still mostly limited to a small number of model organisms, and originates from a wide variety of experimental and computational techniques. The database and online resource STRING generalizes access to protein interaction data, by integrating known and predicted interactions from a variety of sources. The underlying infrastructure includes a consistent body of completely sequenced genomes and exhaustive orthology classifications, based on which interaction evidence is transferred between organisms. Although primarily developed for protein interaction analysis, the resource has also been successfully applied to comparative genomics, phylogenetics and network studies, which are all facilitated by programmatic access to the database backend and the availability of compact download files. As of release 7, STRING has almost doubled to 373 distinct organisms, and contains more than 1.5 million proteins for which associations have been pre-computed. Novel features include AJAX-based web-navigation, inclusion of additional resources such as BioGRID, and detailed protein domain annotation. STRING is available at http://string.embl.de/
339.
Quantification of insect genome divergence.
Zdobnov EM, Bork P
2007 Jan 8; 23(1): 16-20. Epub 2006 Nov 9; PubMed: 17097187.
Abstract + PDFThe recent sequencing of twelve insect genomes has enabled us to quantify their divergence using synteny conservation and sequence identity of single-copy orthologs. Protein identity correlates well with synteny and is about three times more conserved, an observation consistent with comparisons among vertebrates. The observed distribution of the lengths of synteny blocks follows a power law and differs from the expectations of the currently accepted random breakage model. Our results show that there is only limited selection for conservation of gene order and reveal a few hundred genes, proximity among which seems to be vital.
2006 20 publication(s).
338.
mRNA degradation by miRNAs and GW182 requires both CCR4:NOT deadenylase and DCP1:DCP2 decapping complexes.
Behm-Ansmant I, Rehwinkel J, Doerks T, Stark A, Bork P, Izaurralde E
Abstract + PDFMicroRNAs (miRNAs) silence the expression of target genes post-transcriptionally. Their function is mediated by the Argonaute proteins (AGOs), which colocalize to P-bodies with mRNA degradation enzymes. Mammalian P-bodies are also marked by the GW182 protein, which interacts with the AGOs and is required for miRNA function. We show that depletion of GW182 leads to changes in mRNA expression profiles strikingly similar to those observed in cells depleted of the essential Drosophila miRNA effector AGO1, indicating that GW182 functions in the miRNA pathway. When GW182 is bound to a reporter transcript, it silences its expression, bypassing the requirement for AGO1. Silencing by GW182 is effected by changes in protein expression and mRNA stability. Similarly, miRNAs silence gene expression by repressing protein expression and/or by promoting mRNA decay, and both mechanisms require GW182. mRNA degradation, but not translational repression, by GW182 or miRNAs is inhibited in cells depleted of CAF1, NOT1, or the decapping DCP1:DCP2 complex. We further show that the N-terminal GW repeats of GW182 interact with the PIWI domain of AGO1. Our findings indicate that GW182 links the miRNA pathway to mRNA degradation by interacting with AGO1 and promoting decay of at least a subset of miRNA targets.
337.
A global initiative on sharing avian flu data.
Bogner P, Capua I, Cox NJ, Lipman DJ, Aly MM, Auewarakul P, Baltimore D, Bork P, Brown I, Buchy P, Cameron G, Chen HL, Colwell R, Porceddu MC, Couacy-Hymann E, Czifra G, Ganguly NK, Gust ID, Doherty PC, Dulbecco R, Fejzic N, Garcia A, Gojobori T, Hargreaves S, Hashash EBS, Hay A, Joannis T, Johnson M, Jørgensen PH, Kida H, Koch G, Krnjaic D, Kurth R, Lamb RA, Lederberg J, Lim W, Lomlamthong Y, Maaetah H, Ali ASM, Marzuki S, Mettenleiter TC, Minta Z, Mishra AC, Muzio F, Naeem K, Osterhaus A, Pasick J, Peiris M, Perk S, Anh BQ, Ramishvili L, Ramzi ZS, Rojs OZ, Salzberg SL, Sánchez AS, Savic V, Senne D, Sulston J, Swayne DE, Tashiro M, Tufan M, Uzakbaev T, Van den Berg T, Varmus HE, Vitasek J, Webster RG, Wilbanks J, Yilmaz N, Zamora PA
2006 Aug 31; 442: 981. PID: 413.
Abstract + PDFCorrespondence.
The global spread of the H5N1 avian influenza virus has already extensively damaged economies worldwide and food safety in developing countries. The spread of infection to new ecosystems results in adaptation of the virus to new hosts, including humans, which amplifies the potential for a flu pandemic. Because it is recognized that avian influenza viruses may be the progenitors of the next human pandemic virus, their genetic evolution should be tracked in detail and promptly investigated.
336.
Computational characterization of multiple Gag-like human proteins.
2006 Nov 15; 22(11): 585-9. Epub 2006 Sep 18; PubMed: 16979784.
Abstract + PDFIn a genome-wide analysis, we have identified 85 human genes encoding 103 protein isoforms that resemble retroviral Gag proteins. These genes were domesticated from retrotransposons in at least five independent events during vertebrate evolution and were subsequently duplicated further in mammals. Structural insights into the mammalian proteins can be inferred by homology to Gag from viruses such as HIV; in turn, the cellular roles of the mammalian Gag homologs, such as apoptosis-related functions and binding to ubiquitin ligases, might hint at further functionality of viral Gag itself.
335.
Identification and analysis of evolutionarily cohesive functional modules in protein networks.
2006 Mar; 16(3): 374-82. Epub 2006 Jan 31; PubMed: 16449501.
Abstract + PDFThe increasing number of sequenced genomes makes it possible to infer the evolutionary history of functional modules, i.e., groups of proteins that contribute jointly to the same cellular function in a given species. Here we identify and analyze those prokaryotic functional modules, whose composition remains largely unchanged during evolution, and study their properties. Such "cohesive" modules have a large number of internal functional connections, encode genes that tend to be in close proximity in prokaryotic genomes, and correspond to physical complexes or complex functional systems like the flagellar apparatus. Cohesive modules are enriched in processes such as energy and amino acid metabolism, cell motility, and intracellular trafficking, or secretion. By grouping genes into modules we achieve a more precise estimate of their age and find that the young modules are often horizontally transferred between species and are enriched in functions involved in interactions with the environment, implying that they play an important role in the adaptation of species to new environments.
334.
Toward automatic reconstruction of a highly resolved tree of life.
Abstract + PDFWe have developed an automatable procedure for reconstructing the tree of life with branch lengths comparable across all three domains. The tree has its basis in a concatenation of 31 orthologs occurring in 191 species with sequenced genomes. It revealed interdomain discrepancies in taxonomic classification. Systematic detection and subsequent exclusion of products of horizontal gene transfer increased phylogenetic resolution, allowing us to confirm accepted relationships and resolve disputed and preliminary classifications. For example, we place the phylum Acidobacteria as a sister group of delta-Proteobacteria, support a Gram-positive origin of Bacteria, and suggest a thermophilic last universal common ancestor.
333.
Comparative analysis of environmental sequences: potential and challenges.
2006 Mar 29; 361(1467): 519-23. PubMed: 16524840.
Abstract + PDFEnvironmental sequencing, also dubbed metagenomics, is increasingly being used to obtain insights into organismal communities in diverse habitats, and has a variety of potential applications foreseeable in biotechnology and medicine. The first public large-scale data provide already a wealth of information hidden in vast amounts of fragmented pieces of DNA from unknown species residing in these environments. Comparative sequence analysis is essential for the interpretation of such data. However, different layers of complexity that are intrinsic to each sample require the establishment of some baselines for comparison: how to normalize for the differences in phylogenetic and functional diversity, how to avoid biases from incomplete data, and how to deal with differences in species dominance or genome sizes? Here we discuss a few of these items and delineate some simple discriminative sequence properties for four distinct habitats.
332.
Proteome survey reveals modularity of the yeast cell machinery.
Gavin AC, Aloy P, Grandi P, Krause R, Boesche M, Marzioch M, Rau C, Jensen LJ, Bastuck S, Dümpelfeld B, Edelmann A, Heurtier MA, Hoffman V, Hoefert C, Klein K, Hudak M, Michon AM, Schelder M, Schirle M, Remor M, Rudi T, Hooper SD, Bauer A, Bouwmeester T, Casari G, Drewes G, Neubauer G, Rick JM, Kuster B, Bork P, Russell RB, Superti-Furga G
Abstract + PDFProtein complexes are key molecular entities that integrate multiple gene products to perform cellular functions. Here we report the first genome-wide screen for complexes in an organism, budding yeast, using affinity purification and mass spectrometry. Through systematic tagging of open reading frames (ORFs), the majority of complexes were purified several times, suggesting screen saturation. The richness of the data set enabled a de novo characterization of the composition and organization of the cellular machinery. The ensemble of cellular proteins partitions into 491 complexes, of which 257 are novel, that differentially combine with additional attachment proteins or protein modules to enable a diversification of potential functions. Support for this modular organization of the proteome comes from integration with available data on expression, localization, function, evolutionary conservation, protein structure and binary interactions. This study provides the largest collection of physically determined eukaryotic cellular machines so far and a platform for biological data integration and modelling.
331.
Insights into social insects from the genome of the honeybee Apis mellifera.
Honeybee Genome Sequencing Consortium , Weinstock GM, Robinson GE, Gibbs RA, Worley KC, Evans JD, Maleszka R, Robertson HM, Weaver DB, Beye M, Bork P, Elsik CG, Hartfelder K, Hunt GJ, Zdobnov EM, Amdam GV, Bitondi MMG, Collins AM, Cristino AS, Lattorff HMG, Lobo CH, Moritz RFA, Nunes FMF, Page RE, Simoes ZLP, Wheeler D, Carninci P, Fukuda S, Hayashizaki Y, Kai C, Kawai J, Sakazume N, Sasaki D, Tagami M, Albert S, Baggerman G, Beggs KT, Bloch G, Cazzamali G, Cohen M, Drapeau MD, Eisenhardt D, Emore C, Ewing MA, Fahrbach SE, Foret S, Grimmelikhuijzen CJP, Hauser F, Hummon AB, Huybrechts J, Jones AK, Kadowaki T, Kaplan N, Kucharski R, Leboulle G, Linial M, Littleton JT, Mercer AR, Richmond TA, Rodriguez-Zas SL, Rubin EB, Sattelle DB, Schlipalius D, Schoofs L, Shemesh Y, Sweedler JV, Velarde R, Verleyen P, Vierstraete E, Williamson MR, Ament SA, Brown SJ, Corona M, Dearden PK, Dunn WA, Elekonich MM, Fujiyuki T, Gattermeier I, Gempe T, Hasselmann M, Kadowaki T, Kage E, Kamikouchi A, Kubo T, Kucharski R, Kunieda T, Lorenzen M, Milshina NV, Morioka M, Ohashi K, Overbeek R, Ross CA, Schioett M, Shippy T, Takeuchi H, Toth AL, Willis JH, Wilson MJ, Gordon KHJ, Letunic I, Hackett K, Peterson J, Felsenfeld A, Guyer M, Solignac M, Agarwala R, Cornuet JM, Monnerot M, Mougel F, Reese JT, Vautrin D, Gillespie JJ, Cannone JJ, Gutell RR, Johnston JS, Eisen MB, Iyer VN, Iyer V, Kosarev P, Mackey AJ, Solovyev V, Souvorov A, Aronstein KA, Bilikova K, Chen YP, Clark AG, Decanini LI, Gelbart WM, Hetru C, Hultmark D, Imler JL, Jiang HB, Kanost M, Kimura K, Lazzaro BP, Lopez DL, Simuth J, Thompson GJ, Zou Z, de Jong P, Sodergren E, Csuros M, Milosavljevic A, Osoegawa K, Richards S, Shu CL, Duret L, Elhaik E, Graur D, Anzola JM, Campbell KS, Childs KL, Collinge D, Crosby MA, Dickens CM, Grametes LS, Grozinger CM, Jones PL, Jorda M, Ling X, Matthews BB, Miller J, Mizzen C, Peinado MA, Reid JG, Russo SM, Schroeder AJ, St Pierre SE, Wang Y, Zhou PL, Jiang HY, Kitts P, Ruef B, Venkatraman A, Zhang L, Aquino-Perez G, Whitfield CW, Behura SK, Berlocher SH, Sheppard WS, Smith DR, Suarez AV, Tsutsui ND, Wei XH, Wheeler D, Havlak P, Li BS, Liu Y, Sodergren E, Jolivet A, Lee S, Nazareth LV, Pu LL, Thorn R, Stolc V, Newman T, Samanta M, Tongprasit WA, Claudianos C, Berenbaum MR, Biswas S, de Graaf DC, Feyereisen R, Johnson RM, Oakeshott JG, Ranson H, Schuler MA, Muzny D, Chacko J, Davis C, Dinh H, Gill R, Hernandez J, Hines S, Hume J, Jackson L, Kovar C, Lewis L, Miner G, Morgan M, Nguyen N, Okwuonu G, Paul H, Santibanez J, Savery G, Svatek A, Villasana D, Wright R, Honeybee Genome Sequencing Consortium
Abstract + PDFHere we report the genome sequence of the honeybee Apis mellifera, a key model for social behaviour and essential to global ecology through pollination. Compared with other sequenced insect genomes, the A. mellifera genome has high A+T and CpG contents, lacks major transposon families, evolves more slowly, and is more similar to vertebrates for circadian rhythm, RNA interference and DNA methylation genes, among others. Furthermore, A. mellifera has fewer genes for innate immunity, detoxification enzymes, cuticle-forming proteins and gustatory receptors, more genes for odorant receptors, and novel genes for nectar and pollen utilization, consistent with its ecology and social organization. Compared to Drosophila, genes in early developmental pathways differ in Apis, whereas similarities exist for functions that differ markedly, such as sex determination, brain function and behaviour. Population genetics suggests a novel African origin for the species A. mellifera and insights into whether Africanized bees spread throughout the New World via hybridization or displacement.
330.
Co-evolution of transcriptional and post-translational cell-cycle regulation.
Jensen LJ, Jensen TS, de Lichtenberg U, Brunak S, Bork P
Abstract + PDFDNA microarray studies have shown that hundreds of genes are transcribed periodically during the mitotic cell cycle of humans, budding yeast, fission yeast and the plant Arabidopsis thaliana. Here we show that despite the fact the protein complexes involved in this process are largely the same among all eukaryotes, their regulation has evolved considerably. Our comparative analysis of several large-scale data sets reveals that although the regulated subunits of each protein complex are expressed just before its time of action, the identity of the periodically expressed proteins differs significantly between organisms. Moreover, we show that these changes in transcriptional regulation have co-evolved with post-translational control independently in several lineages; loss or gain of cell-cycle-regulated transcription of specific genes is often mirrored by changes in phosphorylation of the proteins that they encode. Our results indicate that many different solutions have evolved for assembling the same molecular machines at the right time during the cell cycle, involving both transcriptional and post-translational layers that jointly control the dynamics of biological systems.
329.
Literature mining for the biologist: from information retrieval to biological discovery.
Jensen LJ, Saric J, Bork P
2006 Feb; 7(2): 119-29. PubMed: 16418747.
Abstract + PDFFor the average biologist, hands-on literature mining currently means a keyword search in PubMed. However, methods for extracting biomedical facts from the scientific literature have improved considerably, and the associated tools will probably soon be used in many laboratories to automatically annotate and analyse the growing number of system-wide experimental data sets. Owing to the increasing body of text and the open-access policies of many journals, literature mining is also becoming useful for both hypothesis generation and biological discovery. However, the latter will require the integration of literature and high-throughput data, which should encourage close collaborations between biologists and computational linguists.
328.
SMART 5: domains in the context of genomes and networks.
2006 Jan 1; 34(Database issue): D257-60. PubMed: 16381859.
Abstract + PDFThe Simple Modular Architecture Research Tool (SMART) is an online resource (http://smart.embl.de/) used for protein domain identification and the analysis of protein domain architectures. Many new features were implemented to make SMART more accessible to scientists from different fields. The new 'Genomic' mode in SMART makes it easy to analyze domain architectures in completely sequenced genomes. Domain annotation has been updated with a detailed taxonomic breakdown and a prediction of the catalytic activity for 50 SMART domains is now available, based on the presence of essential amino acids. Furthermore, intrinsically disordered protein regions can be identified and displayed. The network context is now displayed in the results page for more than 350 000 proteins, enabling easy analyses of domain interactions.
327.
Literature and genome data mining for prioritizing disease-associated genes.
In: Discovering biomolecular mechanisms with computational biology. (Edited by F. Einsenhaber) pp.74-81. BID: 19.
ISBN: 0-387-34527-2 Publisher: Springer Science+Business Media, New York, New York, USA.
AbstractThe first step in understanding the molecular biology of an inherited disease is to identify which gene or genes are carrying variants. This process starts with locating the mutations in a chromosomal band, as narrow as possible, and follows with the manual analysis of all the genes mapping in this region. Usually this is not an easy task, but it can be facilitated by complementary computational approaches that evaluate all genes in a region of interest. We present here a method that combines literature mining, gene annotations, and sequence homology searches to prioritize candidate genes involved in a given genetic disorder. The method progresses in two steps. Firstly, we compute associations of molecular and phenotypic features as taken from MEDLINE. Secondly, for a disease with a given phenotype and linked to a chromosomal region, sequence homology based searches are carried on the chromosomal region to identify potential candidates that are scored using the precomputed associations. The scoring of associations between biological concepts using links across databases can be extended to other databases in Molecular Biology and to nondisease phenotypes.
326.
Assessing Systems Properties of Yeast Mitochondria through an Interaction Map of the Organelle.
2006 Oct 20; 2(10): e170. PubMed: 17054397.
Abstract + PDFMitochondria carry out specialized functions; compartmentalized, yet integrated into the metabolic and signaling processes of the cell. Although many mitochondrial proteins have been identified, understanding their functional interrelationships has been a challenge. Here we construct a comprehensive network of the mitochondrial system. We integrated genome-wide datasets to generate an accurate and inclusive mitochondrial parts list. Together with benchmarked measures of protein interactions, a network of mitochondria was constructed in their cellular context, including extra-mitochondrial proteins. This network also integrates data from different organisms to expand the known mitochondrial biology beyond the information in the existing databases. Our network brings together annotated and predicted functions into a single framework. This enabled, for the entire system, a survey of mutant phenotypes, gene regulation, evolution, and disease susceptibility. Furthermore, we experimentally validated the localization of several candidate proteins and derived novel functional contexts for hundreds of uncharacterized proteins. Our network thus advances the understanding of the mitochondrial system in yeast and identifies properties of genes underlying human mitochondrial disorders.
325.
Opsins and clusters of sensory G-protein-coupled receptors in the sea urchin genome.
Raible F, Tessmar-Raible K, Arboleda E, Kaller T, Bork P, Arendt D, Arnone MI
Abstract + PDFRhodopsin-type G-protein-coupled receptors (GPCRs) contribute the majority of sensory receptors in vertebrates. With 979 members, they form the largest GPCR family in the sequenced sea urchin genome, constituting more than 3% of all predicted genes. The sea urchin genome encodes at least six Opsin proteins. Of these, one rhabdomeric, one ciliary and two G(o)-type Opsins can be assigned to ancient bilaterian Opsin subfamilies. Moreover, we identified four greatly expanded subfamilies of rhodopsin-type GPCRs that we call sea urchin specific rapidly expanded lineages of GPCRs (surreal-GPCRs). Our analysis of two of these groups revealed genomic clustering and single-exon gene structures similar to the most expanded group of vertebrate rhodopsin-type GPCRs, the olfactory receptors. We hypothesize that these genes arose by rapid duplication in the echinoid lineage and act as chemosensory receptors of the animal. In support of this, group B surreal-GPCRs are most prominently expressed in distinct classes of pedicellariae and tube feet of the adult sea urchin, structures that have previously been shown to react to chemical stimuli and to harbor sensory neurons in echinoderms. Notably, these structures also express different opsins, indicating that sea urchins possess an intricate molecular set-up to sense their environment.
324.
A temporal map of transcription factor activity: mef2 directly regulates target genes at all stages of muscle development.
Sandmann T, Jensen LJ, Jakobsen JS, Karzynski MM, Eichenlaub MP, Bork P, Furlong EE
Abstract + PDFDissecting components of key transcriptional networks is essential for understanding complex developmental processes and phenotypes. Genetic studies have highlighted the role of members of the Mef2 family of transcription factors as essential regulators in myogenesis from flies to man. To understand how these transcription factors control diverse processes in muscle development, we have combined chromatin immunoprecipitation analysis with gene expression profiling to obtain a temporal map of Mef2 activity during Drosophila embryonic development. This global approach revealed three temporal patterns of Mef2 enhancer binding, providing a glimpse of dynamic enhancer use within the context of a developing embryo. Our results provide mechanistic insight into the regulation of Mef2's activity at the level of DNA binding and suggest cooperativity with the bHLH protein Twist. The number and diversity of new direct target genes indicates a much broader role for Mef2, at all stages of myogenesis, than previously anticipated.
323.
Extraction of regulatory gene/protein networks from Medline.
2006 Mar 15; 22(6): 645-50. Epub 2005 Jul 26; PubMed: 16046493.
Abstract + PDFMOTIVATION: We have previously developed a rule based approach for extracting information on the regulation of gene expression in yeast. The biomedical literature, however, contains information on several other equally important regulatory mechanisms, in particular phosphorylation, which we now expanded our rule based system to also extract. RESULTS: This paper presents new results for extraction of relational information from biomedical text. We have improved our system, STRING-IE, to both capture new types of linguistic constructs as well as new types of biological information (i.e. (de-)phosphorylation). The precision remains stable with a slight increase in recall. From almost one million PubMed abstracts related to four model organisms, we manage to extract regulatory networks and binary phosphorylations comprising 3319 relation chunks. The accuracy is 83-90% and 86-95% for gene expression and (de-)phosphorylation relations, respectively. To achieve this, we made use of an organism-specific resource of gene/protein names considerably larger than those used in most other biology related information extraction approaches. These names were included in the lexicon when retraining the part-of-speech tagger on the GENIA corpus. For the domain in question an accuracy of 96.4% was attained on POS-tags. It should be noted that the rules were developed for yeast and successfully applied to both abstracts and full-text articles related to other organisms with comparable accuracy. AVAILABILITY: The revised GENIA corpus, the POS-tagger, the extraction rules, and the full sets of extracted relations are available from http://www.bork.embl.de/Docu/STRING-IE.
322.
LSAT: learning about alternative transcripts in MEDLINE.
Shah PK, Bork P
2006 Apr 1; 22(7): 857-65. Epub 2006 Jan 12; PubMed: 16410322.
Abstract + PDFMOTIVATION: Generation of alternative transcripts from the same gene in is an important biological event due to their contribution in creating functional diversity in eukaryotes. In this work, we choose the task of extracting information around this complex topic using a two step procedure involving machine learning and information extraction. RESULTS: In the first step, we trained a classifier that inductively learns to identify sentences about physiological transcript diversity from the MEDLINE abstracts. Using a large hand-built corpus, we compared the sentence classification performance of various text categorization methods. Support vector machines (SVM) followed by the maximum entropy classifier outperformed other methods for the sentence classification task. The SVM with the radial basis function kernel and optimized parameters achieved Fbeta-measure of 91% during the four-fold cross validation and of 74% when applied to all sentences in more than 12 million abstracts of MEDLINE. In the second step, we identified eight frequently present semantic categories in the sentences and performed a limited amount of semantic role labeling. The role labeling step also achieved very high Fbeta-measure for all eight categories. AVAILABILITY: The results of our two-step procedure are summarized in the LSAT database of alternative transcripts. LSAT is available at http://www.bork.embl.de/LSAT/.
321.
Identification and analysis of genes and pseudogenes within duplicated regions in the human and mouse genomes.
2006 Jun 30; 2(6): e76. Epub 2006 May 16; PubMed: 16846249.
Abstract + PDFThe identification and classification of genes and pseudogenes in duplicated regions still constitutes a challenge for standard automated genome annotation procedures. Using an integrated homology and orthology analysis independent of current gene annotation, we have identified 9,484 and 9,017 gene duplicates in human and mouse, respectively. On the basis of the integrity of their coding regions, we have classified them into functional and inactive duplicates, allowing us to define the first consistent and comprehensive collection of 1,811 human and 1,581 mouse unprocessed pseudogenes. Furthermore, of the total of 14,172 human and mouse duplicates predicted to be functional genes, as many as 420 are not included in current reference gene databases and therefore correspond to likely novel mammalian genes. Some of these correspond to partial duplicates with less than half of the length of the original source genes, yet they are conserved and syntenic among different mammalian lineages. The genes and unprocessed pseudogenes obtained here will enable further studies on the mechanisms involved in gene duplication as well as of the fate of duplicated genes.
320.
PAL2NAL: robust conversion of protein sequence alignments into the corresponding codon alignments.
2006 Jul 1; 34(Web Server issue): W609-12. PubMed: 16845082.
Abstract + PDFPAL2NAL is a web server that constructs a multiple codon alignment from the corresponding aligned protein sequences. Such codon alignments can be used to evaluate the type and rate of nucleotide substitutions in coding DNA for a wide range of evolutionary analyses, such as the identification of levels of selective constraint acting on genes, or to perform DNA-based phylogenetic studies. The server takes a protein sequence alignment and the corresponding DNA sequences as input. In contrast to other existing applications, this server is able to construct codon alignments even if the input DNA sequence has mismatches with the input protein sequence, or contains untranslated regions and polyA tails. The server can also deal with frame shifts and inframe stop codons in the input models, and is thus suitable for the analysis of pseudogenes. Another distinct feature is that the user can specify a subregion of the input alignment in order to specifically analyze functional domains or exons of interest. The PAL2NAL server is available at http://www.bork.embl.de/pal2nal.
319.
Similar gene expression profiles do not imply similar tissue functions.
2006 Mar; 22(3): 132-8. Epub 2006 Feb 9; PubMed: 16480787.
Abstract + PDFAlthough similarities in gene expression among tissues are commonly inferred to reflect functional constraints, this has never been formally tested. Furthermore, it is unclear which evolutionary processes are responsible for the observed similarities. When examining genome-wide expression data in mouse, we found that patterns of expression similarity between tissues extend to genes that are unlikely to function in the tissues. Thus, ectopic expression can seem coordinated across tissues. This indicates that knowledge of gene expression patterns per se is insufficient to infer gene function. Ectopic expression is possibly explained as expression leakage, caused by spreading of chromatin modifications or the transcription apparatus into neighboring genes.
2005 28 publication(s).
318.
Is there biological research beyond Systems Biology? A comparative analysis of terms.
Bork P
2005; 1: 2005.0012. PubMed: 16729047.
PDF316.
Comparative architectures of mammalian and chicken genomes reveal highly variable rates of genomic rearrangements across different lineages.
Bourque G, Zdobnov EM, Bork P, Pevzner PA, Tesler G
Abstract + PDFMolecular evolution studies are usually based on the analysis of individual genes and thus reflect only small-range variations in genomic sequences. A complementary approach is to study the evolutionary history of rearrangements in entire genomes based on the analysis of gene orders. The progress in whole genome sequencing provides an unprecedented level of detailed sequence data to infer genome rearrangements through comparative approaches. The comparative analysis of recently sequenced rodent genomes with the human genome revealed evidence for a larger number of rearrangements than previously thought and led to the reconstruction of the putative genomic architecture of the murid rodent ancestor, while the architecture of the ancestral mammalian genome and the rate of rearrangements in the human lineage remained unknown. Sequencing the chicken genome provides an opportunity to reconstruct the architecture of the ancestral mammalian genome by using chicken as an outgroup. Our analysis reveals a very low rate of rearrangements and, in particular, interchromosomal rearrangements in chicken, in the early mammalian ancestor, or in both. The suggested number of interchromosomal rearrangements between the mammalian ancestor and chicken, during an estimated 500 million years of evolution, only slightly exceeds the number of interchromosomal rearrangements that happened in the mouse lineage, over the course of about 87 million years.
315.
Structural Genomics of human proteins - target selection and generation of a public catalog of expression clones.
Bussow K, Scheich C, Sievert V, Harttig U, Schultz J, Simon B, Bork P, Lehrach H, Heinemann U
2005 Jul 5; 4: 21. Epub 2005 Jul 5; PubMed: 15998469.
Abstract + PDFBACKGROUND: The availability of suitable recombinant protein is still a major bottleneck in protein structure analysis. The Protein Structure Factory, part of the international structural genomics initiative, targets human proteins for structure determination. It has implemented high throughput procedures for all steps from cloning to structure calculation. This article describes the selection of human target proteins for structure analysis, our high throughput cloning strategy, and the expression of human proteins in Escherichia coli host cells. RESULTS AND CONCLUSION: Protein expression and sequence data of 1414 E. coli expression clones representing 537 different proteins are presented. 139 human proteins (18%) could be expressed and purified in soluble form and with the expected size. All E. coli expression clones are publicly available to facilitate further functional characterisation of this set of human proteins.
314.
The WHy domain mediates the response to desiccation in plants and bacteria.
Ciccarelli FD, Bork P
2005 Apr 15; 21(8): 1304-7. Epub 2004 Dec 14; PubMed: 15598830.
Abstract + PDFMOTIVATION: The hypersensitive response (HR) is a process activated by plants after microbial infection. Its main phenotypic effects are both a programmed death of the plant cells near the infection site and a reduction of the microbial proliferation. Although many resistance genes (R genes) associated to HR have been identified, very little is known about the molecular mechanisms activated after their expression. RESULTS: The analysis of the product of one of the R genes, the Hin1 protein, led to the identification of a novel domain, which we named WHy because it is detectable in proteins involved in Water stress and Hypersensitive response. The expression of this domain during both biotic infection and response to desiccation points to a molecular machinery common to these two stress conditions. Moreover, its presence in a restricted number of bacteria suggests a possible use for marking plant pathogenicity. CONTACT: francesca.ciccarelli@embl.de SUPPLEMENTARY INFORMATION: Supplementary data (Figures S1 and S2 and Table S1) and the alignment in clustal format are available at http://www.bork.embl.de/~ciccarel/WHy_add_data.html.
313.
Complex genomic rearrangements lead to novel primate gene function.
Abstract + PDFOrthologous genes that maintain a single-copy status in a broad range of species may indicate a selection against gene duplication. If this is the case, then duplicates of such genes that do survive may have escaped the dosage control by rapid and sizable changes in their function. To test this hypothesis and to develop a strategy for the identification of novel gene functions, we have analyzed 22 primate-specific intrachromosomal duplications of genes with a single-copy ortholog in all other completely sequenced metazoans. When comparing this set to genes not exposed to the single-copy status constraint, we observed a higher tendency of the former to modify their gene structure, often through complex genomic rearrangements. The analysis of the most dramatic of these duplications, affecting approximately 10% of human Chromosome 2, enabled a detailed reconstruction of the events leading to the appearance of a novel gene family. The eight members of this family originated from the highly conserved nucleoporin RanBP2 by several genetic rearrangements such as segmental duplications, inversions, translocations, exon loss, and domain accretion. We have experimentally verified that at least one of the newly formed proteins has a cellular localization different from RanBP2's, and we show that positive selection did act on specific domains during evolution.
312.
Dynamic complex formation during the yeast cell cycle.
de Lichtenberg U, Jensen LJ, Brunak S, Bork P
Abstract + PDFTo analyze the dynamics of protein complexes during the yeast cell cycle, we integrated data on protein interactions and gene expression. The resulting time-dependent interaction network places both periodically and constitutively expressed proteins in a temporal cell cycle context, thereby revealing previously unknown components and modules. We discovered that most complexes consist of both periodically and constitutively expressed subunits, which suggests that the former control complex activity by a mechanism of just-in-time assembly. Consistent with this, we show that additional regulation through targeted degradation and phosphorylation by Cdc28p (Cdk1) specifically affects the periodically expressed proteins.
311.
Comparison of computational methods for the identification of cell cycle-regulated genes.
de Lichtenberg U, Jensen LJ, Fausbøll A, Jensen TS, Bork P, Brunak S
2005 Apr 1; 21(7): 1164-71. Epub 2004 Oct 28; PubMed: 15513999.
Abstract + PDFMOTIVATION: DNA microarrays have been used extensively to study the cell cycle transcription programme in a number of model organisms. The Saccharomyces cerevisiae data in particular have been subjected to a wide range of bioinformatics analysis methods, aimed at identifying the correct and complete set of periodically expressed genes. RESULTS: Here, we provide the first thorough benchmark of such methods, surprisingly revealing that most new and more mathematically advanced methods actually perform worse than the analysis published with the original microarray data sets. We show that this loss of accuracy specifically affects methods that only model the shape of the expression profile without taking into account the magnitude of regulation. We present a simple permutation-based method that performs better than most existing methods.
310.
Environments shape the nucleotide composition of genomes.
Abstract + PDFTo test the impact of environments on genome evolution, we analysed the relative abundance of the nucleotides guanine and cytosine ('GC content') of large numbers of sequences from four distinct environmental samples (ocean surface water, farm soil, an acidophilic mine drainage biofilm and deep-sea whale carcasses). We show that the GC content of complex microbial communities seems to be globally and actively influenced by the environment. The observed nucleotide compositions cannot be easily explained by distinct phylogenetic origins of the species in the environments; the genomic GC content may change faster than was previously thought, and are also reflected in the amino-acid composition of the proteins in these habitats.
309.
Generation and annotation of the DNA sequences of human chromosomes 2 and 4.
Hillier LW, Graves TA, Fulton RS, Fulton LA, Pepin KH, Minx P, Wagner-McPherson C, Layman D, Wylie K, Sekhon M, Becker MC, Fewell GA, Delehaunty KD, Miner TL, Nash WE, Kremitzki C, Oddy L, Du H, Sun H, Bradshaw-Cordum H, Ali J, Carter J, Cordes M, Harris A, Isak A, van Brunt A, Nguyen C, Du F, Courtney L, Kalicki J, Ozersky P, Abbott S, Armstrong J, Belter EA, Caruso L, Cedroni M, Cotton M, Davidson T, Desai A, Elliott G, Erb T, Fronick C, Gaige T, Haakenson W, Haglund K, Holmes A, Harkins R, Kim K, Kruchowski SS, Strong CM, Grewal N, Goyea E, Hou S, Levy A, Martinka S, Mead K, McLellan MD, Meyer R, Randall-Maher J, Tomlinson C, Dauphin-Kohlberg S, Kozlowicz-Reilly A, Shah N, Swearengen-Shahid S, Snider J, Strong JT, Thompson J, Yoakum M, Leonard S, Pearman C, Trani L, Radionenko M, Waligorski JE, Wang C, Rock SM, Tin-Wollam AM, Maupin R, Latreille P, Wendl MC, Yang SP, Pohl C, Wallis JW, Spieth J, Bieri TA, Berkowicz N, Nelson JO, Osborne J, Ding L, Meyer R, Sabo A, Shotland Y, Sinha P, Wohldmann PE, Cook LL, Hickenbotham MT, Eldred J, Williams D, Jones TA, She X, Ciccarelli FD, Izaurralde E, Taylor J, Schmutz J, Myers RM, Cox DR, Huang X, McPherson JD, Mardis ER, Clifton SW, Warren WC, Chinwalla AT, Eddy SR, Marra MA, Ovcharenko I, Furey TS, Miller W, Eichler EE, Bork P, Suyama M, Torrents D, Waterston RH, Wilson RK
Abstract + PDFHuman chromosome 2 is unique to the human lineage in being the product of a head-to-head fusion of two intermediate-sized ancestral chromosomes. Chromosome 4 has received attention primarily related to the search for the Huntington's disease gene, but also for genes associated with Wolf-Hirschhorn syndrome, polycystic kidney disease and a form of muscular dystrophy. Here we present approximately 237 million base pairs of sequence for chromosome 2, and 186 million base pairs for chromosome 4, representing more than 99.6% of their euchromatic sequences. Our initial analyses have identified 1,346 protein-coding genes and 1,239 pseudogenes on chromosome 2, and 796 protein-coding genes and 778 pseudogenes on chromosome 4. Extensive analyses confirm the underlying construction of the sequence, and expand our understanding of the structure and evolution of mammalian chromosomes, including gene deserts, segmental duplications and highly variant regions.
308.
Medusa: a simple tool for interaction graph analysis.
Hooper SD, Bork P
2005 Dec 15; 21(24): 4432-3. Epub 2005 Sep 27; PubMed: 16188923.
Abstract + PDFSUMMARY: Medusa is a java application for visualizing and manipulating graphs of interaction, such as data from the STRING database. It features an intuitive user interface developed with the help of biologists. Medusa is optimized for accessing protein interaction data from STRING, but can be used for any type of graph from any scientific field. AVAILABILITY: Medusa, along with sample data sets and instructions, can be downloaded from http://www.bork.embl.de/medusa.
307.
Systematic association of genes to phenotypes by genome and literature mining.
Abstract + PDFOne of the major challenges of functional genomics is to unravel the connection between genotype and phenotype. So far no global analysis has attempted to explore those connections in the light of the large phenotypic variability seen in nature. Here, we use an unsupervised, systematic approach for associating genes and phenotypic characteristics that combines literature mining with comparative genome analysis. We first mine the MEDLINE literature database for terms that reflect phenotypic similarities of species. Subsequently we predict the likely genomic determinants: genes specifically present in the respective genomes. In a global analysis involving 92 prokaryotic genomes we retrieve 323 clusters containing a total of 2,700 significant gene-phenotype associations. Some clusters contain mostly known relationships, such as genes involved in motility or plant degradation, often with additional hypothetical proteins associated with those phenotypes. Other clusters comprise unexpected associations; for example, a group of terms related to food and spoilage is linked to genes predicted to be involved in bacterial food poisoning. Among the clusters, we observe an enrichment of pathogenicity-related associations, suggesting that the approach reveals many novel genes likely to play a role in infectious diseases.
306.
Computational Analysis of Modular Protein Architectures
Linding R, Letunic I, Gibson TJ, Bork P
In: Modular Protein Domains (Ed. Giovanni Cesareni, Mario Gimona, Marius Sudol, and Michael Yaffe)BID: 21.
ISBN: 3-527-30813-2 Publisher: Wiley-VCH Verlag GmbH & Co, KGaA Weinheim
Abstract + PDFAbout the bioinformatics and computational tools for finding modular domains and their cognate ligands.
305.
Very-KIND is a novel nervous system specific guanine nucleotide exchange factor for Ras GTPases.
Mees A, Rock R, Ciccarelli FD, Leberfinger CB, Borawski JM, Bork P, Wiese S, Gessler M, Kerkhoff E
2005 Dec; 6(1): 79-85. Epub 2005 Aug 15; PubMed: 16099729.
Abstract + PDFThe kinase non-catalytic c-lobe domain (KIND) evolved from the catalytic protein kinase fold into a potential protein interaction module for signalling proteins. Spir family actin organizers and the non-receptor phosphatase type 13 (PTP type 13) encode a KIND domain in the very N-terminal parts of the proteins. Here we report the characterization and cloning of a third member of the KIND protein family, which we have named very-KIND (VKIND) because of its two KIND domains. Like the other members of the protein family, VKIND has a KIND domain at the N-terminus. A second KIND domain is located in the central part of the protein. The C-terminal half encodes a guanine nucleotide exchange factor motif for Ras-like GTPases (RasGEF) and a RasGEF N-terminal module (RasGEFN). There is only one VKIND gene in the mammalian genomes and up to now we have found the gene only in vertebrates. During mouse embryogenesis the VKIND gene was specifically expressed in the developing nervous system. In adult mice Northern hybridizations revealed high expression only in brain. Low expression could be detected in ovary. In situ hybridizations showed a specific expression of VKIND in neuronal cells of the granular and Purkinje cell layers of the cerebellum.
304.
Initial sequence of the chimpanzee genome and comparison with the human genome
Mikkelsen TS, Hillier LW, Eichler EE, Zody MC, Jaffe DB, Yang SP, Enard W, Hellmann I, Lindblad-Toh K, Altheide TK, Archidiacono N, Bork P, Butler J, Chang JL, Cheng Z, Chinwalla AT, deJong P, Delehaunty KD, Fronick CC, Fulton LL, Gilad Y, Glusman G, Gnerre S, Graves TA, Hayakawa T, Hayden KE, Huang X, Ji HK, Kent WJ, King MC, Kulbokas III EJ, Lee MK, Liu G, Lopez-Otin C, Makova KD, Man O, Mardis ER, Mauceli E, Miner TL, Nash WE, Nelson JO, Pääbo S, Patterson NJ, Pohl CS, Pollard KS, Prüfer K, Puente XS, Reich D, Rocchi M, Rosenbloom K, Ruvolo M, Richter DJ, Schaffner SF, Smit AFA, Smith SM, Suyama M, Taylor J, Torrents D, Tuzun E, Varki A, Velasco G, Ventura M, Wallis JW, Wendl MC, Wilson RK, Lander ES, Waterston RH
Abstract + PDFHere we present a draft genome sequence of the common chimpanzee (Pan troglodytes). Through comparison with the human genome, we have generated a largely complete catalogue of the genetic differences that have accumulated since the human and chimpanzee species diverged from our common ancestor, constituting approximately thirty-five million single-nucleotide changes, five million insertion/deletion events, and various chromosomal rearrangements. We use this catalogue to explore the magnitude and regional variation of mutational forces shaping these two genomes, and the strength of positive and negative selection acting on their genes. In particular, we find that the patterns of evolution in human and chimpanzee protein-coding genes are highly correlated and dominated by the fixation of neutral and slightly deleterious alleles. We also use the chimpanzee genome as an outgroup to investigate human population genetics and identify signatures of selective sweeps in recent human evolution.
303.
InterPro, progress and status in 2005.
Mulder NJ, Apweiler R, Attwood TK, Bairoch A, Bateman A, Binns D, Bradley P, Bork P, Bucher P, Cerutti L, Copley R, Courcelle E, Das U, Durbin R, Fleischmann W, Gough J, Haft D, Harte N, Hulo N, Kahn D, Kanapin A, Krestyaninova M, Lonsdale D, Lopez R, Letunic I, Madera M, Maslen J, McDowall J, Mitchell A, Nikolskaya AN, Orchard S, Pagni M, Ponting CP, Quevillon E, Selengut J, Sigrist CJ, Silventoinen V, Studholme DJ, Vaughan R, Wu CH
2005 Jan 1; 33(Database issue): D201-5. PubMed: 15608177.
Abstract + PDFInterPro, an integrated documentation resource of protein families, domains and functional sites, was created to integrate the major protein signature databases. Currently, it includes PROSITE, Pfam, PRINTS, ProDom, SMART, TIGRFAMs, PIRSF and SUPERFAMILY. Signatures are manually integrated into InterPro entries that are curated to provide biological and functional information. Annotation is provided in an abstract, Gene Ontology mapping and links to specialized databases. New features of InterPro include extended protein match views, taxonomic range information and protein 3D structure data. One of the new match views is the InterPro Domain Architecture view, which shows the domain composition of protein matches. Two new entry types were introduced to better describe InterPro entries: these are active site and binding site. PIRSF and the structure-based SUPERFAMILY are the latest member databases to join InterPro, and CATH and PANTHER are soon to be integrated. InterPro release 8.0 contains 11 007 entries, representing 2573 domains, 8166 families, 201 repeats, 26 active sites, 21 binding sites and 20 post-translational modification sites. InterPro covers over 78% of all proteins in the Swiss-Prot and TrEMBL components of UniProt. The database is available for text- and sequence-based searches via a webserver (http://www.ebi.ac.uk/interpro), and for download by anonymous FTP (ftp://ftp.ebi.ac.uk/pub/databases/interpro).
302.
G2D: A Tool for Mining Genes Associated with Disease.
Abstract + PDFBACKGROUND: Human inherited diseases can be associated by genetic linkage with one or more genomic regions. The availability of the complete sequence of the human genome allows examining those locations for an associated gene. We previously developed an algorithm to prioritize genes on a chromosomal region according to their possible relation to an inherited disease using a combination of data mining on biomedical databases and gene sequence analysis. RESULTS: We have implemented this method as a web application in our site G2D (Genes to Diseases). It allows users to inspect any region of the human genome to find candidates genes related to a genetic disease of their interest. In addition, the G2D server includes pre-computed analyses of candidate genes for 552 linked monogenic diseases without an associated gene, and the analysis of 18 asthma loci. CONCLUSIONS: G2D can be publicly accessed at http://www.ogic.ca/projects/g2d_2/.
301.
Vertebrate-type intron-rich genes in the marine annelid Platynereis dumerilii.
Raible F, Tessmar-Raible K, Osoegawa K, Wincker P, Jubin C, Balavoine G, Ferrier D, Benes V, de Jong P, Weissenbach J, Bork P, Arendt D
Abstract + PDFPrevious genome comparisons have suggested that one important trend in vertebrate evolution has been a sharp rise in intron abundance. By using genomic data and expressed sequence tags from the marine annelid Platynereis dumerilii, we provide direct evidence that about two-thirds of human introns predate the bilaterian radiation but were lost from insect and nematode genomes to a large extent. A comparison of coding exon sequences confirms the ancestral nature of Platynereis and human genes. Thus, the urbilaterian ancestor had complex, intron-rich genes that have been retained in Platynereis and human.
300.
Nonsense-mediated mRNA decay factors act in concert to regulate common mRNA targets.
Abstract + PDFNonsense-mediated mRNA decay (NMD) is a surveillance pathway that degrades mRNAs containing nonsense codons, and regulates the expression of naturally occurring transcripts. While NMD is not essential in yeast or nematodes, UPF1, a key NMD effector, is essential in mice. Here we show that NMD components are required for cell proliferation in Drosophila. This raises the question of whether NMD effectors diverged functionally during evolution. To address this question, we examined expression profiles in Drosophila cells depleted of all known metazoan NMD components. We show that UPF1, UPF2, UPF3, SMG1, SMG5, and SMG6 regulate in concert the expression of a cohort of genes with functions in a wide range of cellular activities, including cell cycle progression. Only a few transcripts were regulated exclusively by individual factors, suggesting that these proteins act mainly in the NMD pathway and their role in mRNA decay has not diverged substantially. Finally, the vast majority of NMD targets in Drosophila are not orthologs of targets previously identified in yeast or human cells. Thus phenotypic differences observed across species following inhibition of NMD can be largely attributed to changes in the repertoire of regulated genes.
299.
Structural similarity to bridge sequence space: finding new families on the bridges.
Shah PK, Aloy P, Bork P, Russell RB
2005 May; 14(5): 1305-14. PubMed: 15840833.
Abstract + PDFStructures for protein domains have increased rapidly in recent years owing to advances in structural biology and structural genomics projects. New structures are often similar to those solved previously, and such similarities can give insights into function by linking poorly understood families to those that are better characterized. They also allow the possibility of combing information to find still more proteins adopting a similar structure and sometimes a similar function, and to reprioritize families in structural genomics pipelines. We explore this possibility here by preparing merged profiles for pairs of structurally similar, but not necessarily sequence-similar, domains within the SMART and Pfam database by way of the Structural Classification of Proteins (SCOP). We show that such profiles are often able to successfully identify further members of the same superfamily and thus can be used to increase the sensitivity of database searching methods like HMMer and PSI-BLAST. We perform detailed benchmarks using the SMART and Pfam databases with four complete genomes frequently used as annotation benchmarks. We quantify the associated increase in structural information in Swissprot and discuss examples illustrating the applicability of this approach to understand functional and evolutionary relationships between protein families.
298.
Extraction of transcript diversity from scientific literature.
2005 Jun; 1(1): e10. Epub 2005 Jun 24; PubMed: 16103899.
Abstract + PDFTranscript diversity generated by alternative splicing and associated mechanisms contributes heavily to the functional complexity of biological systems. The numerous examples of the mechanisms and functional implications of these events are scattered throughout the scientific literature. Thus, it is crucial to have a tool that can automatically extract the relevant facts and collect them in a knowledge base that can aid the interpretation of data from high-throughput methods. We have developed and applied a composite text-mining method for extracting information on transcript diversity from the entire MEDLINE database in order to create a database of genes with alternative transcripts. It contains information on tissue specificity, number of isoforms, causative mechanisms, functional implications, and experimental methods used for detection. We have mined this resource to identify 959 instances of tissue-specific splicing. Our results in combination with those from EST-based methods suggest that alternative splicing is the preferred mechanism for generating transcript diversity in the nervous system. We provide new annotations for 1,860 genes with the potential for generating transcript diversity. We assign the MeSH term "alternative splicing" to 1,536 additional abstracts in the MEDLINE database and suggest new MeSH terms for other events. We have successfully extracted information about transcript diversity and semiautomatically generated a database, LSAT, that can provide a quantitative understanding of the mechanisms behind tissue-specific gene expression. LSAT (Literature Support for Alternative Transcripts) is publicly available at http://www.bork.embl.de/LSAT/.
297.
Palindromic repetitive DNA elements with coding potential in Methanocaldococcus jannaschii.
Abstract + PDFWe have identified 141 novel palindromic repetitive elements in the genome of euryarchaeon Methanocaldococcus jannaschii. The total length of these elements is 14.3kb, which corresponds to 0.9% of the total genomic sequence and 6.3% of all extragenic regions. The elements can be divided into three groups (MJRE1-3) based on the sequence similarity. The low sequence identity within each of the groups suggests rather old origin of these elements in M. jannaschii. Three MJRE2 elements were located within the protein coding regions without disrupting the coding potential of the host genes, indicating that insertion of repeats might be a widespread mechanism to enhance sequence diversity in coding regions.
296.
Spore number control and breeding in Saccharomyces cerevisiae: a key role for a self-organizing system.
Taxis C, Keller P, Kavagiou Z, Jensen LJ, Colombelli J, Bork P, Stelzer EH, Knop M
2005 Nov 21; 171(4): 627-40. Epub 2005 Nov 14; PubMed: 16286509.
Abstract + PDFSpindle pole bodies (SPBs) provide a structural basis for genome inheritance and spore formation during meiosis in yeast. Upon carbon source limitation during sporulation, the number of haploid spores formed per cell is reduced. We show that precise spore number control (SNC) fulfills two functions. SNC maximizes the production of spores (1-4) that are formed by a single cell. This is regulated by the concentration of three structural meiotic SPB components, which is dependent on available amounts of carbon source. Using experiments and computer simulation, we show that the molecular mechanism relies on a self-organizing system, which is able to generate particular patterns (different numbers of spores) in dependency on one single stimulus (gradually increasing amounts of SPB constituents). We also show that SNC enhances intratetrad mating, whereby maximal amounts of germinated spores are able to return to a diploid lifestyle without intermediary mitotic division. This is beneficial for the immediate fitness of the population of postmeiotic cells.
295.
DCD - a novel plant specific domain in proteins involved in development and programmed cell death.
Tenhaken R, Doerks T, Bork P
2005 Jul 11; 6: 169. Epub 2005 Jul 11; PubMed: 16008837.
Abstract + PDFBACKGROUND: Recognition of microbial pathogens by plants triggers the hypersensitive reaction, a common form of programmed cell death in plants. These dying cells generate signals that activate the plant immune system and alarm the neighboring cells as well as the whole plant to activate defense responses to limit the spread of the pathogen. The molecular mechanisms behind the hypersensitive reaction are largely unknown except for the recognition process of pathogens. We delineate the NRP-gene in soybean, which is specifically induced during this programmed cell death and contains a novel protein domain, which is commonly found in different plant proteins. RESULTS: The sequence analysis of the protein, encoded by the NRP-gene from soybean, led to the identification of a novel domain, which we named DCD, because it is found in plant proteins involved in development and cell death. The domain is shared by several proteins in the Arabidopsis and the rice genomes, which otherwise show a different protein architecture. Biological studies indicate a role of these proteins in phytohormone response, embryo development and programmed cell by pathogens or ozone. CONCLUSIONS: It is tempting to speculate, that the DCD domain mediates signaling in plant development and programmed cell death and could thus be used to identify interacting proteins to gain further molecular insights into these processes.
294.
Comparative metagenomics of microbial communities.
Tringe SG, von Mering C, Kobayashi A, Salamov AA, Chen K, Chang HW, Podar M, Short JM, Mathur EJ, Detter JC, Bork P, Hugenholtz P, Rubin EM
Abstract + PDFThe species complexity of microbial communities and challenges in culturing representative isolates make it difficult to obtain assembled genomes. Here we characterize and compare the metabolic capabilities of terrestrial and marine microbial communities using largely unassembled sequence data obtained by shotgun sequencing DNA isolated from the various environments. Quantitative gene content analysis reveals habitat-specific fingerprints that reflect known characteristics of the sampled environments. The identification of environment-specific genes through a gene-centric comparative analysis presents new opportunities for interpreting and diagnosing environments.
293.
STRING: known and predicted protein-protein associations, integrated and transferred across organisms.
2005 Jan 1; 33(Database issue): D433-7. PubMed: 15608232.
Abstract + PDFA full description of a protein's function requires knowledge of all partner proteins with which it specifically associates. From a functional perspective, 'association' can mean direct physical binding, but can also mean indirect interaction such as participation in the same metabolic pathway or cellular process. Currently, information about protein association is scattered over a wide variety of resources and model organisms. STRING aims to simplify access to this information by providing a comprehensive, yet quality-controlled collection of protein-protein associations for a large number of organisms. The associations are derived from high-throughput experimental data, from the mining of databases and literature, and from predictions based on genomic context analysis. STRING integrates and ranks these associations by benchmarking them against a common reference set, and presents evidence in a consistent and intuitive web interface. Importantly, the associations are extended beyond the organism in which they were originally described, by automatic transfer to orthologous protein pairs in other organisms, where applicable. STRING currently holds 730,000 proteins in 180 fully sequenced organisms, and is available at http://string.embl.de/.
292.
Protein coding potential of retroviruses and other transposable elements in vertebrate genomes.
2005; 33(3): 946-54. PubMed: 15716312.
Abstract + PDFWe suggest an annotation strategy for genes encoded by retroviruses and transposable elements (RETRA genes) based on a set of marker protein domains. Usually RETRA genes are masked in vertebrate genomes prior to the application of automated gene prediction pipelines under the assumption that they provide no selective advantage to the host. Yet, we show that about 1000 genes in four vertebrate gene sets analyzed contain at least one RETRA gene marker domain. Using the conservation of genomic neighborhood (synteny), we were able to discriminate between RETRA genes with putative functionality in the vertebrates and those that probably function only in the context of mobile elements. We identified 35 such genes in human, along with their corresponding mouse and rat orthologs; which included almost all known human genes with similarity to mobile elements. The results also imply that the vast majority of the remaining RETRA genes in current gene sets are unlikely to encode vertebrate functions. To automatically annotate RETRA genes in other vertebrate genomes, we provide as a tool a set of marker protein domains and a manually refined list of domesticated or ancestral RETRA genes for rescuing genes with vertebrate functions.
291.
Consistency of genome-based methods in measuring Metazoan evolution.
Abstract + PDFSeven distinct genome-wide divergence measures were applied pairwise to the nine sequenced animal genomes of human, mouse, rat, chicken, pufferfish, fruit fly, mosquito, and two nematode worms (Caenorhabditis briggsae and Caenorhabditis elegans). Qualitatively, all of these divergence measures are found to correlate with the estimated time since speciation; however, marked deviations are observed in a few lineages. The distinct genome divergence measures also correlate well among themselves, indicating that most of the processes shaping genomes are dominated by neutral events. The deviations from the clock-like scenario in some lineages are observed consistently by several measures, implicitly confirming their reliability.
2004 21 publication(s).
290.
Structure-based assembly of protein complexes in yeast.
Aloy P, Böttcher B, Ceulemans H, Leutwein C, Mellwig C, Fischer S, Gavin AC, Bork P, Superti-Furga G, Serrano L, Russell RB
Abstract + PDFImages of entire cells are preceding atomic structures of the separate molecular machines that they contain. The resulting gap in knowledge can be partly bridged by protein-protein interactions, bioinformatics, and electron microscopy. Here we use interactions of known three-dimensional structure to model a large set of yeast complexes, which we also screen by electron microscopy. For 54 of 102 complexes, we obtain at least partial models of interacting subunits. For 29, including the exosome, the chaperonin containing TCP-1, a 3'-messenger RNA degradation complex, and RNA polymerase II, the process suggests atomic details not easily seen by homology, involving the combination of two or more known structures. We also consider interactions between complexes (cross-talk) and use these to construct a structure-based network of molecular machines in the cell.
289.
Protein interaction networks from yeast to human.
2004 Jun; 14(3): 292-9. PubMed: 15193308.
Abstract + PDFProtein interaction networks summarize large amounts of protein-protein interaction data, both from individual, small-scale experiments and from automated high-throughput screens. The past year has seen a flood of new experimental data, especially on metazoans, as well as an increasing number of analyses designed to reveal aspects of network topology, modularity and evolution. As only minimal progress has been made in mapping the human proteome using high-throughput screens, the transfer of interaction information within and across species has become increasingly important. With more and more heterogeneous raw data becoming available, proper data integration and quality control have become essential for reliable protein network reconstruction, and will be especially important for reconstructing the human protein interaction network.
288.
Genes and structures in context (editorial).
Bork P, Orengo C
2004 June; 14(3): 261-263. PID: 335.
PDF287.
The Helmholtz Network for Bioinformatics: an integrative web portal for bioinformatics resources.
Crass T, Antes I, Basekow R, Bork P, Buning C, Christensen M, Claussen H, Ebeling C, Ernst P, Gailus-Durner V, Glatting KH, Gohla R, Gössling F, Grote K, Heidtke K, Herrmann A, O'Keeffe S, Kiesslich O, Kolibal S, Korbel JO, Lengauer T, Liebich I, van der Linden M, Luz H, Meissner K, von Mering C, Mevissen HT, Mewes HW, Michael H, Mokrejs M, Müller T, Pospisil H, Rarey M, Reich JG, Schneider R, Schomburg D, Schulze-Kremer S, Schwarzer K, Sommer I, Springstubbe S, Suhai S, Thoppae G, Vingron M, Warfsmann J, Werner T, Wetzler D, Wingender E, Zimmer R
2004 Jan 22; 20(2): 268-70. PubMed: 14734319.
Abstract + PDFSUMMARY: The Helmholtz Network for Bioinformatics (HNB) is a joint venture of eleven German bioinformatics research groups that offers convenient access to numerous bioinformatics resources through a single web portal. The 'Guided Solution Finder' which is available through the HNB portal helps users to locate the appropriate resources to answer their queries by employing a detailed, tree-like questionnaire. Furthermore, automated complex tool cascades ('tasks'), involving resources located on different servers, have been implemented, allowing users to perform comprehensive data analyses without the requirement of further manual intervention for data transfer and re-formatting. Currently, automated cascades for the analysis of regulatory DNA segments as well as for the prediction of protein functional properties are provided. AVAILABILITY: The HNB portal is available at http://www.hnbioinfo.de
286.
Global analysis of bacterial transcription factors to predict cellular target processes.
2004 Mar; 20(3): 126-31. PubMed: 15049306.
Abstract + PDFWhole-genome sequences are now available for >100 bacterial species, giving unprecedented power to comparative genomics approaches. We have applied genome-context methods to predict target processes that are regulated by transcription factors (TFs). Of 128 orthologous groups of proteins annotated as TFs, to date, 36 are functionally uncharacterized; in our analysis we predict a probable cellular target process or biochemical pathway for half of these functionally uncharacterized TFs.
285.
Functional clues for hypothetical proteins based on genomic context analysis in prokaryotes.
2004; 32(21): 6321-6. PubMed: 15576358.
Abstract + PDFThree integrated genomic context methods were used to annotate uncharacterized proteins in 102 bacterial genomes. Of 7853 orthologous groups with unknown function containing 45,110 proteins, 1738 groups could be linked to functionally associated partners. In many cases, those partners are uncharacterized themselves (hinting at newly identified modules) or have been described in general terms only. However, we were able to assign pathways, cellular processes or physical complexes for 273 groups (encompassing 3624 previously functionally uncharacterized proteins).
284.
RanBP2/Nup358 provides a major binding site for NXF1-p15 dimers at the nuclear pore complex and functions in nuclear mRNA export.
Forler D, Rabut G, Ciccarelli FD, Herold A, Köcher T, Niggeweg R, Bork P, Ellenberg J, Izaurralde E
2004 Feb; 24(3): 1155-67. PubMed: 14729961.
Abstract + PDFMetazoan NXF1-p15 heterodimers promote the nuclear export of bulk mRNA across nuclear pore complexes (NPCs). In vitro, NXF1-p15 forms a stable complex with the nucleoporin RanBP2/Nup358, a component of the cytoplasmic filaments of the NPC, suggesting a role for this nucleoporin in mRNA export. We show that depletion of RanBP2 from Drosophila cells inhibits proliferation and mRNA export. Concomitantly, the localization of NXF1 at the NPC is strongly reduced and a significant fraction of this normally nuclear protein is detected in the cytoplasm. Under the same conditions, the steady-state subcellular localization of other nuclear or cytoplasmic proteins and CRM1-mediated protein export are not detectably affected, indicating that the release of NXF1 into the cytoplasm and the inhibition of mRNA export are not due to a general defect in NPC function. The specific role of RanBP2 in the recruitment of NXF1 to the NPC is highlighted by the observation that depletion of CAN/Nup214 also inhibits cell proliferation and mRNA export but does not affect NXF1 localization. Our results indicate that RanBP2 provides a major binding site for NXF1 at the cytoplasmic filaments of the NPC, thereby restricting its diffusion in the cytoplasm after NPC translocation. In RanBP2-depleted cells, NXF1 diffuses freely through the cytoplasm. Consequently, the nuclear levels of the protein decrease and export of bulk mRNA is impaired.
283.
Genome sequence of the Brown Norway rat yields insights into mammalian evolution.
Gibbs RA, Weinstock GM, Metzker ML, Muzny DM, Sodergren EJ, Scherer S, Scott G, Steffen D, Worley KC, Burch PE, Okwuonu G, Hines S, Lewis L, DeRamo C, Delgado O, Dugan-Rocha S, Miner G, Morgan M, Hawes A, Gill R, Celera , Holt RA, Adams MD, Amanatides PG, Baden-Tillson H, Barnstead M, Chin S, Evans CA, Ferriera S, Fosler C, Glodek A, Gu Z, Jennings D, Kraft CL, Nguyen T, Pfannkoch CM, Sitter C, Sutton GG, Venter JC, Woodage T, Smith D, Lee HM, Gustafson E, Cahill P, Kana A, Doucette-Stamm L, Weinstock K, Fechtel K, Weiss RB, Dunn DM, Green ED, Blakesley RW, Bouffard GG, De Jong PJ, Osoegawa K, Zhu B, Marra M, Schein J, Bosdet I, Fjell C, Jones S, Krzywinski M, Mathewson C, Siddiqui A, Wye N, McPherson J, Zhao S, Fraser CM, Shetty J, Shatsman S, Geer K, Chen Y, Abramzon S, Nierman WC, Havlak PH, Chen R, Durbin KJ, Egan A, Ren Y, Song XZ, Li B, Liu Y, Qin X, Cawley S, Worley KC, Cooney AJ, D'Souza LM, Martin K, Wu JQ, Gonzalez-Garay ML, Jackson AR, Kalafus KJ, McLeod MP, Milosavljevic A, Virk D, Volkov A, Wheeler DA, Zhang Z, Bailey JA, Eichler EE, Tuzun E, Birney E, Mongin E, Ureta-Vidal A, Woodwark C, Zdobnov EM, Bork P, Suyama M, Torrents D, Alexandersson M, Trask BJ, Young JM, Huang H, Wang H, Xing H, Daniels S, Gietzen D, Schmidt J, Stevens K, Vitt U, Wingrove J, Camara F, Mar Albà M, Abril JF, Guigo R, Smit A, Dubchak I, Rubin EM, Couronne O, Poliakov A, Hübner N, Ganten D, Goesele C, Hummel O, Kreitler T, Lee YA, Monti J, Schulz H, Zimdahl H, Himmelbauer H, Lehrach H, Jacob HJ, Bromberg S, Gullings-Handley J, Jensen-Seaman MI, Kwitek AE, Lazar J, Pasko D, Tonellato PJ, Twigger S, Ponting CP, Duarte JM, Rice S, Goodstadt L, Beatson SA, Emes RD, Winter EE, Webber C, Brandt P, Nyakatura G, Adetobi M, Chiaromonte F, Elnitski L, Eswara P, Hardison RC, Hou M, Kolbe D, Makova K, Miller W, Nekrutenko A, Riemer C, Schwartz S, Taylor J, Yang S, Zhang Y, Lindpaintner K, Andrews TD, Caccamo M, Clamp M, Clarke L, Curwen V, Durbin R, Eyras E, Searle SM, Cooper GM, Batzoglou S, Brudno M, Sidow A, Stone EA, Venter JC, Payseur BA, Bourque G, López-Otín C, Puente XS, Chakrabarti K, Chatterji S, Dewey C, Pachter L, Bray N, Yap VB, Caspi A, Tesler G, Pevzner PA, Haussler D, Roskin KM, Baertsch R, Clawson H, Furey TS, Hinrichs AS, Karolchik D, Kent WJ, Rosenbloom KR, Trumbower H, Weirauch M, Cooper DN, Stenson PD, Ma B, Brent M, Arumugam M, Shteynberg D, Copley RR, Taylor MS, Riethman H, Mudunuri U, Peterson J, Guyer M, Felsenfeld A, Old S, Mockrin S, Collins F, Rat Genome Sequencing Project Consortium
Abstract + PDFThe laboratory rat (Rattus norvegicus) is an indispensable tool in experimental medicine and drug development, having made inestimable contributions to human health. We report here the genome sequence of the Brown Norway (BN) rat strain. The sequence represents a high-quality 'draft' covering over 90% of the genome. The BN rat sequence is the third complete mammalian genome to be deciphered, and three-way comparisons with the human and mouse genomes resolve details of mammalian evolution. This first comprehensive analysis includes genes and proteins and their relation to human disease, repeated sequences, comparative genome-wide studies of mammalian orthologous chromosomal regions and rearrangement breakpoints, reconstruction of ancestral karyotypes and the events leading to existing species, rates of variation, and lineage-specific and lineage-independent evolutionary events such as expansion of gene families, orthology relations and protein evolution.
282.
Estimating rates of alternative splicing in mammals and invertebrates.
2004 Sept; 36(9): 916 - 917. PID: 307.
PDF281.
The HUPO PSI's molecular interaction format--a community standard for the representation of protein interaction data.
Hermjakob H, Montecchi-Palazzi L, Bader G, Wojcik J, Salwinski L, Ceol A, Moore S, Orchard S, Sarkans U, von Mering C, Roechert B, Poux S, Jung E, Mersch H, Kersey P, Lappe M, Li Y, Zeng R, Rana D, Nikolski M, Husi H, Brun C, Shanker K, Grant SG, Sander C, Bork P, Zhu W, Pandey A, Brazma A, Jacq B, Vidal M, Sherman D, Legrain P, Cesareni G, Xenarios I, Eisenberg D, Steipe B, Hogue C, Apweiler R
2004 Feb; 22(2): 177-83. PubMed: 14755292.
Abstract + PDFA major goal of proteomics is the complete description of the protein interaction network underlying cell physiology. A large number of small scale and, more recently, large-scale experiments have contributed to expanding our understanding of the nature of the interaction network. However, the necessary data integration across experiments is currently hampered by the fragmentation of publicly available protein interaction data, which exists in different formats in databases, on authors' websites or sometimes only in print publications. Here, we propose a community standard data model for the representation and exchange of protein interaction data. This data model has been jointly developed by members of the Proteomics Standards Initiative (PSI), a work group of the Human Proteome Organization (HUPO), and is supported by major protein interaction data providers, in particular the Biomolecular Interaction Network Database (BIND), Cellzome (Heidelberg, Germany), the Database of Interacting Proteins (DIP), Dana Farber Cancer Institute (Boston, MA, USA), the Human Protein Reference Database (HPRD), Hybrigenics (Paris, France), the European Bioinformatics Institute's (EMBL-EBI, Hinxton, UK) IntAct, the Molecular Interactions (MINT, Rome, Italy) database, the Protein-Protein Interaction Database (PPID, Edinburgh, UK) and the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING, EMBL, Heidelberg, Germany).
280.
Sequence and comparative analysis of the chicken genome provide unique perspectives on vertebrate evolution.
Hillier LW, Miller W, Birney E, Warren W, Hardison RC, Ponting CP, Bork P, Burt DW, Groenen MA, Delany ME, Dodgson JB, Chinwalla AT, Cliften PF, Clifton SW, Delehaunty KD, Fronick C, Fulton RS, Graves TA, Kremitzki C, Layman D, Magrini V, McPherson JD, Miner TL, Minx P, Nash WE, Nhan MN, Nelson JO, Oddy LG, Pohl CS, Randall-Maher J, Smith SM, Wallis JW, Yang SP, Romanov MN, Rondelli CM, Paton B, Smith J, Morrice D, Daniels L, Tempest HG, Robertson L, Masabanda JS, Griffin DK, Vignal A, Fillon V, Jacobbson L, Kerje S, Andersson L, Crooijmans RP, Aerts J, van der Poel JJ, Ellegren H, Caldwell RB, Hubbard SJ, Grafham DV, Kierzek AM, McLaren SR, Overton IM, Arakawa H, Beattie KJ, Bezzubov Y, Boardman PE, Bonfield JK, Croning MD, Davies RM, Francis MD, Humphray SJ, Scott CE, Taylor RG, Tickle C, Brown WR, Rogers J, Buerstedde JM, Wilson SA, Stubbs L, Ovcharenko I, Gordon L, Lucas S, Miller MM, Inoko H, Shiina T, Kaufman J, Salomonsen J, Skjoedt K, Wong GK, Wang J, Liu B, Wang J, Yu J, Yang H, Nefedov M, Koriabine M, Dejong PJ, Goodstadt L, Webber C, Dickens NJ, Letunic I, Suyama M, Torrents D, von Mering C, Zdobnov EM, Makova K, Nekrutenko A, Elnitski L, Eswara P, King DC, Yang S, Tyekucheva S, Radakrishnan A, Harris RS, Chiaromonte F, Taylor J, He J, Rijnkels M, Griffiths-Jones S, Ureta-Vidal A, Hoffman MM, Severin J, Searle SM, Law AS, Speed D, Waddington D, Cheng Z, Tuzun E, Eichler E, Bao Z, Flicek P, Shteynberg DD, Brent MR, Bye JM, Huckle EJ, Chatterji S, Dewey C, Pachter L, Kouranov A, Mourelatos Z, Hatzigeorgiou AG, Paterson AH, Ivarie R, Brandstrom M, Axelsson E, Backstrom N, Berlin S, Webster MT, Pourquie O, Reymond A, Ucla C, Antonarakis SE, Long M, Emerson JJ, Betrán E, Dupanloup I, Kaessmann H, Hinrichs AS, Bejerano G, Furey TS, Harte RA, Raney B, Siepel A, Kent WJ, Haussler D, Eyras E, Castelo R, Abril JF, Castellano S, Camara F, Parra G, Guigo R, Bourque G, Tesler G, Pevzner PA, Smit A, Fulton LA, Mardis ER, Wilson RK, International Chicken Genome Sequencing Consortium
Abstract + PDFWe present here a draft genome sequence of the red jungle fowl, Gallus gallus. Because the chicken is a modern descendant of the dinosaurs and the first non-mammalian amniote to have its genome sequenced, the draft sequence of its genome--composed of approximately one billion base pairs of sequence and an estimated 20,000-23,000 genes--provides a new perspective on vertebrate genome evolution, while also improving the annotation of mammalian genomes. For example, the evolutionary distance between chicken and human provides high specificity in detecting functional elements, both non-coding and coding. Notably, many conserved non-coding sequences are far from genes and cannot be assigned to defined functional classes. In coding regions the evolutionary dynamics of protein domains and orthologous groups illustrate processes that distinguish the lineages leading to birds and mammals. The distinctive properties of avian microchromosomes, together with the inferred patterns of conserved synteny, provide additional insights into vertebrate chromosome architecture.
279.
Quality analysis and integration of large scale molecular data sets.
Jensen LJ, Bork P
2004 Apr; 3(2): 51-56. PID: 308.
PDF278.
ArrayProspector: a web resource of functional associations inferred from microarray expression data.
2004 Jul 1; 32(Web Server issue): W445-8. PubMed: 15215427.
Abstract + PDFDNA microarray experiments have provided vast amounts of data which can be used for inferring gene function. However, most methods for predicting functional associations between genes from expression data are not suited to simultaneous analysis of multiple datasets, and a comprehensive resource of coexpression-based predictions is currently lacking. Here, we present an interactive web resource of gene associations predicted by applying a novel algorithm to all expression data in the Stanford Microarray Database. The underlying pre-computed database currently contains more than 200 000 high-confidence gene associations in 12 different species sampled from a broad taxonomic range. The resource allows every association to be inspected visually and can be accessed at http://www.bork.embl.de/ArrayProspector.
277.
Gene expression profiling of the rat superior olivary complex using serial analysis of gene expression.
Koehl A, Schmidt N, Rieger A, Pilgram SM, Letunic I, Bork P, Soto F, Friauf E, Nothwang HG
2004 Dec; 20(12): 3244-58. PubMed: 15610157.
Abstract + PDFThe superior olivary complex (SOC) is an auditory brainstem region that represents a favourable system to study rapid neurotransmission and the maturation of neuronal circuits. Here we performed serial analysis of gene expression (SAGE) on the SOC in 60-day-old Sprague-Dawley rats to identify genes specifically important for its function and to create a transcriptome reference for the subsequent identification of age-related or disease-related changes. Sequencing of 31 035 tags identified 10 473 different transcripts. Fifty-seven per cent of the unique tags with a count greater than four were statistically more highly represented in the SOC than in the hippocampus. Among them were genes encoding proteins involved in energy supply, the glutamate/glutamine shuttle, and myelination. Approximately 80 plasma membrane transporters, receptors, channels, and vesicular transporters were identified, and 25% of them displayed a significantly higher expression level in the SOC than in the hippocampus. Some of the plasma membrane proteins were not previously characterized in the SOC, e.g. the purinergic receptor subunit P2X(6) and the metabotropic GABA receptor Gpr51. Differential gene expression between SOC and hippocampus was confirmed using RNA in situ hybridization or immunohistochemistry. The extensive gene inventory presented here will alleviate the dissection of the molecular mechanisms underlying specific SOC functions and the comparison with other SAGE libraries from brain will ease the identification of promoters to generate region-specific transgenic animals. The analysis will be part of the publicly available database ID-GRAB.
276.
Analysis of genomic context: prediction of functional associations from conserved bidirectionally transcribed gene pairs.
2004 Jul; 22(7): 911-7. PubMed: 15229555.
Abstract + PDFSeveral widely used methods for predicting functional associations between proteins are based on the systematic analysis of genomic context. Efforts are ongoing to improve these methods and to search for novel aspects in genomes that could be exploited for function prediction. Here, we use gene expression data to demonstrate two functional implications of genome organization: first, chromosomal proximity indicates gene coregulation in prokaryotes independent of relative gene orientation; and second, adjacent bidirectionally transcribed genes (that is,'divergently' organized coding regions) with conserved gene orientation are strongly coregulated. We further demonstrate that such bidirectionally transcribed gene pairs are functionally associated and derive from this a novel genomic context method that reliably predicts links between >2,500 pairs of genes in approximately 100 species. Around 650 of these functional associations are supported by other genomic context methods. In most instances, one gene encodes a transcriptional regulator, and the other a nonregulatory protein. In-depth analysis in Escherichia coli shows that the vast majority of these regulators both control transcription of the divergently transcribed target gene/operon and auto-regulate their own biosynthesis. The method thus enables the prediction of target processes and regulatory features for several hundred transcriptional regulators.
275.
Shared components of protein complexes--versatile building blocks or biochemical artefacts?
Abstract + PDFProtein complexes perform many important functions in the cell. Large-scale studies of protein-protein interactions have not only revealed new complexes but have also placed many proteins into multiple complexes. Whilst the advocates of hypothesis-free research touted the discovery of these shared components as new links between diverse cellular processes, critical commentators denounced many of the findings as artefacts, thus questioning the usefulness of large-scale approaches. Here, we survey proteins known to be shared between complexes, as established in the literature, and compare them to shared components found in high-throughput screens. We discuss the various challenges to the identification and functional interpretation of bona fide shared components, namely contaminants, variant and megacomplexes, and transient interactions, and suggest that many of the novel shared components found in high-throughput screens are neither the results of contamination nor central components, but appear to be primarily regulatory links in cellular processes.
274.
SMART 4.0: towards genomic data integration.
2004 Jan 1; 32(Database issue): D142-4. PubMed: 14681379.
Abstract + PDFSMART (Simple Modular Architecture Research Tool) is a web tool (http://smart.embl.de/) for the identification and annotation of protein domains, and provides a platform for the comparative study of complex domain architectures in genes and proteins. The January 2004 release of SMART contains 685 protein domains. New developments in SMART are centred on the integration of data from completed metazoan genomes. SMART now uses predicted proteins from complete genomes in its source sequence databases, and integrates these with predictions of orthology. New visualization tools have been developed to allow analysis of gene intron-exon structure within the context of protein domain structure, and to align these displays to provide schematic comparisons of orthologous genes, or multiple transcripts from the same gene. Other improvements include the ability to query SMART by Gene Ontology terms, improved structure database searching and batch retrieval of multiple entries.
273.
Homology-based functional proteomics by mass spectrometry: application to the Xenopus microtubule-associated proteome.
Liska AJ, Popov AV, Sunyaev SR, Coughlin P, Habermann B, Shevchenko A, Bork P, Karsenti E, Shevchenko A
2004 Sep; 4(9): 2707-21. PubMed: 15352245.
Abstract + PDFThe application of functional proteomics to important model organisms with unsequenced genomes is restricted because of the limited ability to identify proteins by conventional mass spectrometry (MS) methods. Here we applied MS and sequence-similarity database searching strategies to characterize the Xenopus laevis microtubule-associated proteome. We identified over 40 unique, and many novel, microtubule-bound proteins, as well as two macromolecular protein complexes involved in protein translation. This finding was corroborated by electron microscopy showing the presence of ribosomes on spindles assembled from frog egg extracts. Taken together, these results suggest that protein translation occurs on the spindle during meiosis in the Xenopus oocyte. These findings were made possible due to the application of sequence-similarity methods, which extended mass spectrometric protein identification capabilities by 2-fold compared to conventional methods.
272.
Gene annotation from scientific literature using mappings between keyword systems.
2004 Sep 1; 20(13): 2084-91. Epub 2004 Apr 1; PubMed: 15059832.
Abstract + PDFMOTIVATION: The description of genes in databases by keywords helps the non-specialist to quickly grasp the properties of a gene and increases the efficiency of computational tools that are applied to gene data (e.g. searching a gene database for sequences related to a particular biological process). However, the association of keywords to genes or protein sequences is a difficult process that ultimately implies examination of the literature related to a gene. RESULTS: To support this task, we present a procedure to derive keywords from the set of scientific abstracts related to a gene. Our system is based on the automated extraction of mappings between related terms from different databases using a model of fuzzy associations that can be applied with all generality to any pair of linked databases. We tested the system by annotating genes of the SWISS-PROT database with keywords derived from the abstracts linked to their entries (stored in the MEDLINE database of scientific references). The performance of the annotation procedure was much better for SWISS-PROT keywords (recall of 47%, precision of 68%) than for Gene Ontology terms (recall of 8%, precision of 67%). AVAILABILITY: The algorithm can be publicly accessed and used for the annotation of sequences through a web server at http://www.bork.embl.de/kat
270.
BLAST2GENE: a comprehensive conversion of BLAST output into independent genes and gene fragments.
2004 Aug 12; 20(12): 1968-70. Epub 2004 Mar 22; PubMed: 15037510.
Abstract + PDFSUMMARY: BLAST2GENE is a program that allows a detailed analysis of genomic regions containing completely or partially duplicated genes. From a BLAST (or BL2SEQ) comparison of a protein or nucleotide query sequence with any genomic region of interest, BLAST2GENE processes all high scoring pairwise alignments (HSPs) and provides the disposition of all independent copies along the genomic fragment. The results are provided in text and PostScript formats to allow an automatic and visual evaluation of the respective region. AVAILABILITY: The program is available upon request from the authors. A web server of BLAST2GENE is maintained at http://www.bork.embl.de/blast2gene
2003 28 publication(s).
269.
Alternative splicing and evolution.
Abstract + PDFAlternative splicing is a critical post-transcriptional event leading to an increase in the transcriptome diversity. Recent bioinformatics studies revealed a high frequency of alternative splicing. Although the extent of AS conservation among mammals is still being discussed, it has been argued that major forms of alternatively spliced transcripts are much better conserved than minor forms. It suggests that alternative splicing plays a major role in genome evolution allowing new exons to evolve with less constraint.
268.
The KIND module: a putative signalling domain evolved from the C lobe of the protein kinase fold.
Ciccarelli FD, Bork P, Kerkhoff E
2003 Jul; 28(7): 349-52. PubMed: 12877999.
PDF267.
The PAM domain, a multi-protein complex-associated module with an all-alpha-helix fold.
Ciccarelli FD, Izaurralde E, Bork P
2003 Dec 19; 4: 64. Epub 2003 Dec 19; PubMed: 14687415.
Abstract + PDFBACKGROUND: Multimeric protein complexes have a role in many cellular pathways and are highly interconnected with various other proteins. The characterization of their domain composition and organization provides useful information on the specific role of each region of their sequence. RESULTS: We identified a new module, the PAM domain (PCI/PINT associated module), present in single subunits of well characterized multiprotein complexes, like the regulatory lid of the 26S proteasome, the COP-9 signalosome and the Sac3-Thp1 complex. This module is an around 200 residue long domain with a predicted TPR-like all-alpha-helical fold. CONCLUSIONS: The occurrence of the PAM domain in specific subunits of multimeric protein complexes, together with the role of other all-alpha-helical folds in protein-protein interactions, suggest a function for this domain in mediating transient binding to diverse target proteins.
266.
The identification of a conserved domain in both spartin and spastin, mutated in hereditary spastic paraplegia.
Ciccarelli FD, Proukakis C, Patel H, Cross H, Azam S, Patton MA, Bork P, Crosby AH
Abstract + PDFMultiple sequence alignment has revealed the presence of a sequence domain of approximately 80 amino acids in two molecules, spartin and spastin, mutated in hereditary spastic paraplegia. The domain, which corresponds to a slightly extended version of the recently described ESP domain of unknown function, was also identified in VPS4, SKD1, RPK118, and SNX15, all of which have a well established and consistent role in endosomal trafficking. Recent functional information indicates that spastin is likely to be involved in microtubule interaction. With this new information relating to its likely function, we propose the more descriptive name 'MIT' (contained within microtubule-interacting and trafficking molecules) for the domain and predict endosomal trafficking as the principal functionality of all molecules in which it is present.
265.
Nonsense-mediated mRNA decay in Drosophila: at the intersection of the yeast and mammalian pathways.
Gatfield D, Unterholzner L, Ciccarelli FD, Bork P, Izaurralde E
Abstract + PDFThe nonsense-mediated mRNA decay (NMD) pathway promotes the rapid degradation of mRNAs containing premature stop codons (PTCs). In Caenorhabditis elegans, seven genes (smg1-7) playing an essential role in NMD have been identified. Only SMG2-4 (known as UPF1-3) have orthologs in Saccharomyces cerevisiae. Here we show that the Drosophila orthologs of UPF1-3, SMG1, SMG5 and SMG6 are required for the degradation of PTC-containing mRNAs, but that there is no SMG7 ortholog in this organism. In contrast, orthologs of SMG5-7 are encoded by the human genome and all three are required for NMD. In human cells, exon boundaries have been shown to play a critical role in defining PTCs. This role is mediated by components of the exon junction complex (EJC). Contrary to expectation, however, we show that the components of the EJC are dispensable for NMD in Drosophila cells. Consistently, PTC definition occurs independently of exon boundaries in DROSOPHILA: Our findings reveal that despite conservation of the NMD machinery, different mechanisms have evolved to discriminate premature from natural stop codons in metazoa.
264.
The DNA sequence of human chromosome 7.
Hillier LW, Fulton RS, Fulton LA, Graves TA, Pepin KH, Wagner-McPherson C, Layman D, Maas J, Jaeger S, Walker R, Wylie K, Sekhon M, Becker MC, O'Laughlin MD, Schaller ME, Fewell GA, Delehaunty KD, Miner TL, Nash WE, Cordes M, Du H, Sun H, Edwards J, Bradshaw-Cordum H, Ali J, Andrews S, Isak A, Vanbrunt A, Nguyen C, Du F, Lamar B, Courtney L, Kalicki J, Ozersky P, Bielicki L, Scott K, Holmes A, Harkins R, Harris A, Strong CM, Hou S, Tomlinson C, Dauphin-Kohlberg S, Kozlowicz-Reilly A, Leonard S, Rohlfing T, Rock SM, Tin-Wollam AM, Abbott A, Minx P, Maupin R, Strowmatt C, Latreille P, Miller N, Johnson D, Murray J, Woessner JP, Wendl MC, Yang SP, Schultz BR, Wallis JW, Spieth J, Bieri TA, Nelson JO, Berkowicz N, Wohldmann PE, Cook LL, Hickenbotham MT, Eldred J, Williams D, Bedell JA, Mardis ER, Clifton SW, Chissoe SL, Marra MA, Raymond C, Haugen E, Gillett W, Zhou Y, James R, Phelps K, Iadanoto S, Bubb K, Simms E, Levy R, Clendenning J, Kaul R, Kent WJ, Furey TS, Baertsch RA, Brent MR, Keibler E, Flicek P, Bork P, Suyama M, Bailey JA, Portnoy ME, Torrents D, Chinwalla AT, Gish WR, Eddy SR, McPherson JD, Olson MV, Eichler EE, Green ED, Waterston RH, Wilson RK
Abstract + PDFHuman chromosome 7 has historically received prominent attention in the human genetics community, primarily related to the search for the cystic fibrosis gene and the frequent cytogenetic changes associated with various forms of cancer. Here we present more than 153 million base pairs representing 99.4% of the euchromatic sequence of chromosome 7, the first metacentric chromosome completed so far. The sequence has excellent concordance with previously established physical and genetic maps, and it exhibits an unusual amount of segmentally duplicated sequence (8.2%), with marked differences between the two arms. Our initial analyses have identified 1,150 protein-coding genes, 605 of which have been confirmed by complementary DNA sequences, and an additional 941 pseudogenes. Of genes confirmed by transcript sequences, some are polymorphic for mutations that disrupt the reading frame.
263.
Function prediction and protein networks.
2003 Apr; 15(2): 191-8. PubMed: 12648675.
Abstract + PDFIn the genomics era, the interactions between proteins are at the center of attention. Genomic-context methods used to predict these interactions have been put on a quantitative basis, revealing that they are at least on an equal footing with genomics experimental data. A survey of experimentally confirmed predictions proves the applicability of these methods, and new concepts to predict protein interactions in eukaryotes have been described. Finally, the interaction networks that can be obtained by combining the predicted pair-wise interactions have enough internal structure to detect higher levels of organization, such as 'functional modules'.
262.
Bioinformatics in the post-sequence era.
Kanehisa M, Bork P
Abstract + PDFIn the past decade, bioinformatics has become an integral part of research and development in the biomedical sciences. Bioinformatics now has an essential role both in deciphering genomic, transcriptomic and proteomic data generated by high-throughput experimental technologies and in organizing information gathered from traditional biology. Sequence-based methods of analyzing individual genes or proteins have been elaborated and expanded, and methods have been developed for analyzing large numbers of genes or proteins simultaneously, such as in the identification of clusters of related genes and networks of interacting proteins. With the complete genome sequences for an increasing number of organisms at hand, bioinformatics is beginning to provide both conceptual bases and practical methods for detecting systemic functional behaviors of the cell and the organism.
261.
A comprehensive set of protein complexes in yeast: mining large scale protein-protein interaction screens.
2003 Oct 12; 19(15): 1901-8. PubMed: 14555622.
Abstract + PDFMOTIVATION: The analysis of protein-protein interactions allows for detailed exploration of the cellular machinery. The biochemical purification of protein complexes followed by identification of components by mass spectrometry is currently the method, which delivers the most reliable information--albeit that the data sets are still difficult to interpret. Consolidating individual experiments into protein complexes, especially for high-throughput screens, is complicated by many contaminants, the occurrence of proteins in otherwise dissimilar purifications due to functional re-use and technical limitations in the detection. A non-redundant collection of protein complexes from experimental data would be useful for biological interpretation, but manual assembly is tedious and often inconsistent. RESULTS: Here, we introduce a measure to define similarity within collections of purifications and generate a set of minimally redundant, comprehensive complexes using unsupervised clustering. AVAILABILITY: Programs and results are freely available from http://www.bork.embl-heidelberg.de/Docu/purclust/
260.
Increase of functional diversity by alternative splicing.
Kriventseva EV, Koch I, Apweiler R, Vingron M, Bork P, Gelfand MS, Sunyaev SR
2003 Mar; 19(3): 124-8. PubMed: 12615003.
Abstract + PDFA large-scale analysis of protein isoforms arising from alternative splicing shows that alternative splicing tends to insert or delete complete protein domains more frequently than expected by chance, whereas disruption of domains and other structural modules is less frequent. If domain regions are disrupted, the functional effect, as predicted from 3D structure, is frequently equivalent to removal of the entire domain. Also, short alternative splicing events within domains, which might preserve folded structure, target functional residues more frequently than expected. Thus, it seems that positive selection has had a major role in the evolution of alternative splicing.
259.
Protein disorder prediction: implications for structural proteomics.
Linding R, Jensen LJ, Diella F, Bork P, Gibson TJ, Russell RB
Abstract + PDFA great challenge in the proteomics and structural genomics era is to predict protein structure and function, including identification of those proteins that are partially or wholly unstructured. Disordered regions in proteins often contain short linear peptide motifs (e.g., SH3 ligands and targeting signals) that are important for protein function. We present here DisEMBL, a computational tool for prediction of disordered/unstructured regions within a protein sequence. As no clear definition of disorder exists, we have developed parameters based on several alternative definitions and introduced a new one based on the concept of "hot loops," i.e., coils with high temperature factors. Avoiding potentially disordered segments in protein expression constructs can increase expression, foldability, and stability of the expressed protein. DisEMBL is thus useful for target selection and the design of constructs as needed for many biochemical studies, particularly structural biology and structural genomics projects. The tool is freely available via a web interface (http://dis.embl.de) and can be downloaded for use in large-scale studies.
258.
Systematic discovery of analogous enzymes in thiamin biosynthesis.
2003 Jul; 21(7): 790-5. Epub 2003 Jun 8; PubMed: 12794638.
Abstract + PDFIn all genome-sequencing projects completed to date, a considerable number of 'gaps' have been found in the biochemical pathways of the respective species. In many instances, missing enzymes are displaced by analogs, functionally equivalent proteins that have evolved independently and lack sequence and structural similarity. Here we fill such gaps by analyzing anticorrelating occurrences of genes across species. Our approach, applied to the thiamin biosynthesis pathway comprising approximately 15 catalytic steps, predicts seven instances in which known enzymes have been displaced by analogous proteins. So far we have verified four predictions by genetic complementation, including three proteins for which there was no previous experimental evidence of a role in the thiamin biosynthesis pathway. For one hypothetical protein, biochemical characterization confirmed the predicted thiamin phosphate synthase (ThiE) activity. The results demonstrate the ability of our computational approach to predict specific functions without taking into account sequence similarity.
257.
High rate of gene displacement in vitamine biosynthetic pathways.
Morett E, Saab-Rincon G, Merino E, Bork P, Rajan E, Olvera L, Olvera M
In: Bioinformatics and genomes. (M. Andrade eds.) pp. 69-79. BID: 3.
Publisher: Horizon Sci. Press
PDF256.
The InterPro Database, 2003 brings increased coverage and new features.
Mulder NJ, Apweiler R, Attwood TK, Bairoch A, Barrell D, Bateman A, Binns D, Biswas M, Bradley P, Bork P, Bucher P, Copley RR, Courcelle E, Das U, Durbin R, Falquet L, Fleischmann W, Griffiths-Jones S, Haft D, Harte N, Hulo N, Kahn D, Kanapin A, Krestyaninova M, Lopez R, Letunic I, Lonsdale D, Silventoinen V, Orchard SE, Pagni M, Peyruc D, Ponting CP, Selengut JD, Servant F, Sigrist CJ, Vaughan R, Zdobnov EM
2003 Jan 1; 31(1): 315-8. PubMed: 12520011.
Abstract + PDFInterPro, an integrated documentation resource of protein families, domains and functional sites, was created in 1999 as a means of amalgamating the major protein signature databases into one comprehensive resource. PROSITE, Pfam, PRINTS, ProDom, SMART and TIGRFAMs have been manually integrated and curated and are available in InterPro for text- and sequence-based searching. The results are provided in a single format that rationalises the results that would be obtained by searching the member databases individually. The latest release of InterPro contains 5629 entries describing 4280 families, 1239 domains, 95 repeats and 15 post-translational modifications. Currently, the combined signatures in InterPro cover more than 74% of all proteins in SWISS-PROT and TrEMBL, an increase of nearly 15% since the inception of InterPro. New features of the database include improved searching capabilities and enhanced graphical user interfaces for visualisation of the data. The database is available via a webserver (http://www.ebi.ac.uk/interpro) and anonymous FTP (ftp://ftp.ebi.ac.uk/pub/databases/interpro).
254.
A protocol for the update of references to scientific literature in biological databases.
2003; 2(3): 189-91. PubMed: 15130808.
Abstract + PDFEntries in biological databases are usually linked to scientific references. To generate those links and to keep them up-to-date, database maintainers have to continuously scan the scientific literature to select references that are relevant for each single database entry. The continuous growth of both the corpus of scientific literature and the size of biological databases makes this task very hard. We present a protocol intended to assist the updating of an existing set of literature (abstract) links from a single database entry with new references. It consists of taking the set of MEDLINE neighbour references of the existing linked abstracts and evaluating their relevance according to the existing set of abstracts. To test the applicability of the algorithm, we did a simple benchmark of the system using the references associated with the entries of a protein domain database. Human experts found the references that the algorithm scored highly were more relevant to the database entry than those scored lowly, suggesting that the algorithm was useful.
253.
Update on XplorMed: A web server for exploring scientific literature.
2003 Jul 1; 31(13): 3866-8. PubMed: 12824439.
Abstract + PDFAs scientific literature databases like MEDLINE increase in size, so does the time required to search them. Scientists must frequently inspect long lists of references manually, often just reading the titles. XplorMed is a web tool that aids MEDLINE searching by summarizing the subjects contained in the results, thus allowing users to focus on subjects of interest. Here we describe new features added to XplorMed during the last 2 years (http://www.bork.embl-heidelberg.de/xplormed/).
252.
ELM server: A new resource for investigating short functional sites in modular eukaryotic proteins.
Puntervoll P, Linding R, Gemünd C, Chabanis-Davidson S, Mattingsdal M, Cameron S, Martin DM, Ausiello G, Brannetti B, Costantini A, Ferrè F, Maselli V, Via A, Cesareni G, Diella F, Superti-Furga G, Wyrwicz L, Ramu C, McGuigan C, Gudavalli R, Letunic I, Bork P, Rychlewski L, Küster B, Helmer-Citterich M, Hunter WN, Aasland R, Gibson TJ
2003 Jul 1; 31(13): 3625-30. PubMed: 12824381.
Abstract + PDFMultidomain proteins predominate in eukaryotic proteomes. Individual functions assigned to different sequence segments combine to create a complex function for the whole protein. While on-line resources are available for revealing globular domains in sequences, there has hitherto been no comprehensive collection of small functional sites/motifs comparable to the globular domain resources, yet these are as important for the function of multidomain proteins. Short linear peptide motifs are used for cell compartment targeting, protein-protein interaction, regulation by phosphorylation, acetylation, glycosylation and a host of other post-translational modifications. ELM, the Eukaryotic Linear Motif server at http://elm.eu.org/, is a new bioinformatics resource for investigating candidate short non-globular functional motifs in eukaryotic proteins, aiming to fill the void in bioinformatics tools. Sequence comparisons with short motifs are difficult to evaluate because the usual significance assessments are inappropriate. Therefore the server is implemented with several logical filters to eliminate false positives. Current filters are for cell compartment, globular domain clash and taxonomic range. In favourable cases, the filters can reduce the number of retained matches by an order of magnitude or more.
251.
Metabolites: a helping hand for pathway evolution?
2003 Jun; 28(6): 336-41. PubMed: 12826406.
Abstract + PDFThe evolution of enzymes and pathways is under debate. Recent studies show that recruitment of single enzymes from different pathways could be the driving force for pathway evolution. Other mechanisms of evolution, such as pathway duplication, enzyme specialization, de novo invention of pathways or retro-evolution of pathways, appear to be less abundant. Twenty percent of enzyme superfamilies are quite variable, not only in changing reaction chemistry or metabolite type but in changing both at the same time. These variable superfamilies account for nearly half of all known reactions. The most frequently occurring metabolites provide a helping hand for such changes because they can be accommodated by many enzyme superfamilies. Thus, a picture is emerging in which new pathways are evolving from central metabolites by preference, thereby keeping the overall topology of the metabolic network.
250.
Information extraction from full text scientific articles: where are the keywords?
2003 May 29; 4: 20. Epub 2003 May 29; PubMed: 12775220.
Abstract + PDFBACKGROUND: To date, many of the methods for information extraction of biological information from scientific articles are restricted to the abstract of the article. However, full text articles in electronic version, which offer larger sources of data, are currently available. Several questions arise as to whether the effort of scanning full text articles is worthy, or whether the information that can be extracted from the different sections of an article can be relevant. RESULTS: In this work we addressed those questions showing that the keyword content of the different sections of a standard scientific article (abstract, introduction, methods, results, and discussion) is very heterogeneous. CONCLUSIONS: Although the abstract contains the best ratio of keywords per total of words, other sections of the article may be a better source of biologically relevant data.
249.
Nanoelectrospray tandem mass spectrometry and sequence similarity searching for identification of proteins from organisms with unknown genomes.
Shevchenko A, Sunyaev SR, Liska A, Bork P, Shevchenko A
2003; 211: 221-34. PubMed: 12489434.
PDF248.
Impact of selection, mutation rate and genetic drift on human genetic variation.
2003 Dec 15; 12(24): 3325-30. Epub 2003 Oct 21; PubMed: 14570704.
Abstract + PDFThe accumulation of genome-wide information on single nucleotide polymorphisms in humans provides an unprecedented opportunity to detect the evolutionary forces responsible for heterogeneity of the level of genetic variability across loci. Previous studies have shown that history of recombination events has produced long haplotype blocks in the human genome, which contribute to this heterogeneity. Other factors, however, such as natural selection or the heterogeneity of mutation rates across loci, may also lead to heterogeneity of genetic variability. We compared synonymous and non-synonymous variability within human genes with their divergence from murine orthologs. We separately analyzed the non-synonymous variants predicted to damage protein structure or function and the variants predicted to be functionally benign. The predictions were based on comparative sequence analysis and, in some cases, on the analysis of protein structure. A strong correlation between non-synonymous, benign variability and non-synonymous human-mouse divergence suggests that selection played an important role in shaping the pattern of variability in coding regions of human genes. However, the lack of correlation between deleterious variability and evolutionary divergence shows that a substantial proportion of the observed non-synonymous single-nucleotide polymorphisms reduces fitness and never reaches fixation. Evolutionary and medical implications of the impact of selection on human polymorphisms are discussed.
247.
Pseudogenes and Genomes.
In: Bioinformatics and genomes. (M. Andrade eds.) pp.197-209. BID: 4.
Publisher: Horizon Sci. Press
PDF246.
A genome-wide survey of human pseudogenes.
2003 Dec; 13(12): 2559-67. PubMed: 14656963.
Abstract + PDFWe screened all intergenic regions in the human genome to identify pseudogenes with a combination of homology searches and a functionality test using the ratio of silent to replacement nucleotide substitutions (KA/KS). We identified 19,724 regions of which 95% +/- 3% are estimated to evolve neutrally and thus are likely to encode pseudogenes. Half of these have no detectable truncation in their pseudocoding regions and therefore are not identifiable by methods that require the presence of truncations to prove nonfunctionality. A comparative analysis with the mouse genome showed that 70% of these pseudogenes have a retrotranspositional origin (processed), and the rest arose by segmental duplication (nonprocessed). Although the spread of both types of pseudogenes correlates with chromosome size, nonprocessed pseudogenes appear to be enriched in regions with high gene density. It is likely that the human pseudogenes identified here represent only a small fraction of the total, which probably exceeds the number of genes.
245.
STRING: a database of predicted functional associations between proteins.
2003 Jan 1; 31(1): 258-61. PubMed: 12519996.
Abstract + PDFFunctional links between proteins can often be inferred from genomic associations between the genes that encode them: groups of genes that are required for the same function tend to show similar species coverage, are often located in close proximity on the genome (in prokaryotes), and tend to be involved in gene-fusion events. The database STRING is a precomputed global resource for the exploration and analysis of these associations. Since the three types of evidence differ conceptually, and the number of predicted interactions is very large, it is essential to be able to assess and compare the significance of individual predictions. Thus, STRING contains a unique scoring-framework based on benchmarks of the different types of associations against a common reference set, integrated in a single confidence score per prediction. The graphical representation of the network of inferred, weighted protein interactions provides a high-level view of functional linkage, facilitating the analysis of modularity in biological processes. STRING is updated continuously, and currently contains 261 033 orthologs in 89 fully sequenced genomes. The database predicts functional interactions at an expected level of accuracy of at least 80% for more than half of the genes; it is online at http://www.bork.embl-heidelberg.de/STRING/.
244.
Genome evolution reveals biochemical networks and functional modules.
2003 Dec 23; 100(26): 15428-33. Epub 2003 Dec 12; PubMed: 14673105.
Abstract + PDFThe analysis of completely sequenced genomes uncovers an astonishing variability between species in terms of gene content and order. During genome history, the genes are frequently rear-ranged, duplicated, lost, or transferred horizontally between genomes. These events appear to be stochastic, yet they are under selective constraints resulting from the functional interactions between genes. These genomic constraints form the basis for a variety of techniques that employ systematic genome comparisons to predict functional associations among genes. The most powerful techniques to date are based on conserved gene neighborhood, gene fusion events, and common phylogenetic distributions of gene families. Here we show that these techniques, if integrated quantitatively and applied to a sufficiently large number of genomes, have reached a resolution which allows the characterization of function at a higher level than that of the individual gene: global modularity becomes detectable in a functional protein network. In Escherichia coli, the predicted modules can be bench-marked by comparison to known metabolic pathways. We found as many as 74% of the known metabolic enzymes clustering together in modules, with an average pathway specificity of at least 84%. The modules extend beyond metabolism, and have led to hundreds of reliable functional predictions both at the protein and pathway level. The results indicate that modularity in protein networks is intrinsically encoded in present-day genomes.
243.
The human genome: genes, pseudogenes, and variation on chromosome 7.
Waterston RH, Hillier LW, Fulton LA, Fulton RS, Graves TA, Pepin KH, Bork P, Suyama M, Torrents D, Chinwalla AT, Mardis ER, McPherson JD, Wilson RK
2003; 68: 13-22. PubMed: 15338598.
PDF242.
Pathogenesis of DNA repair-deficient cancers: a statistical meta-analysis of putative Real Common Target genes.
Woerner SM, Benner A, Sutter C, Schiller M, Yuan YP, Keller G, Bork P, Doeberitz MK, Gebert JF
Abstract + PDFDNA mismatch repair deficiency is observed in about 15% of human colorectal, gastric, and endometrial tumors and in lower frequencies in a minority of other tumors thereby causing insertion/deletion mutations at short repetitive sequences, recognized as microsatellite instability (MSI). Evolution of tumors, including those with MSI, is a continuous process of mutation and selection favoring neoplastic growth. Mutations in microsatellite-bearing genes that promote tumor cell growth in general (Real Common Target genes) are assumed to be the driving force during MSI carcinogenesis. Thus, microsatellite mutations in these genes should occur more frequently than mutations in microsatellite genes without contribution to malignancy (ByStander genes). So far, only a few Real Common Target genes have been identified by functional studies. Thus, comprehensive analysis of microsatellite mutations will provide important clues to the understanding of MSI-driven carcinogenesis. Here, we evaluated published mutation frequencies on 194 repeat tracts in 137 genes in MSI-H colorectal, endometrial, and gastric carcinomas and propose a statistical model that aims to identify Real Common Target genes. According to our model nine genes including BAX and TGFbetaRII were identified as Real Common Targets in colorectal cancer, one gene in gastric cancer, and three genes in endometrial cancer. Microsatellite mutations in five additional genes seem to be counterselected in gastrointestinal tumors. Overall, the general applicability, the capacity to unlimited data analysis, the inclusion of mutation data generated by different groups on different sets of tumors make this model a useful tool for predicting Real Common Target genes with specificity for MSI-H tumors of different organs, guiding subsequent functional studies to the most likely targets among numerous microsatellite harboring genes.
2002 39 publication(s).
241.
A complex prediction: three-dimensional model of the yeast exosome.
Aloy P, Ciccarelli FD, Leutwein C, Gavin AC, Superti-Furga G, Bork P, Bottcher B, Russell RB
Abstract + PDFWe present a model of the yeast exosome based on the bacterial degradosome component polynucleotide phosphorylase (PNPase). Electron microscopy shows the exosome to resemble PNPase but with key differences likely related to the position of RNA binding domains, and to the location of domains unique to the exosome. We use various techniques to reduce the many possible models of exosome subunits based on PNPase to just one. The model suggests numerous experiments to probe exosome function, particularly with respect to subunits making direct atomic contacts and conserved, possibly functional residues within the predicted central pore of the complex.
240.
NEAT: a domain duplicated in genes near the components of a putative Fe3+ siderophore transporter from Gram-positive pathogenic bacteria.
2002 Aug 15; 3(9): RESEARCH0047. Epub 2002 Aug 15; PubMed: 12225586.
Abstract + PDFBACKGROUND: Iron uptake from the host is essential for bacteria that infect animals. To find potential targets for drugs active against pathogenic bacteria, we have searched all completely sequenced genomes of pathogenic bacteria for genes relevant for iron transport. RESULTS: We identified a protein domain that appears in variable copy number in bacterial genes that are usually in the vicinity of a putative Fe3+ siderophore transporter. Accordingly, we have denoted this domain NEAT for 'near transporter'. Most of the bacterial species containing this domain are pathogenic. Sequence features indicate that the domain is anchored to the extracellular side of the membrane. The domain seems to be under high selective pressure for rapid independent duplications that are typical of sequences involved in signaling and binding. CONCLUSIONS: The NEAT domain might be functionally related to iron transport. The taxonomic specificity of this domain and its predicted extracellular position could make it an interesting target for designing new drugs against some highly pathogenic bacteria.
239.
The rhodanese/Cdc25 phosphatase superfamily. Sequence-structure-function relations.
Bordo D, Bork P
Abstract + PDFRhodanese domains are ubiquitous structural modules occurring in the three major evolutionary phyla. They are found as tandem repeats, with the C-terminal domain hosting the properly structured active-site Cys residue, as single domain proteins or in combination with distinct protein domains. An increasing number of reports indicate that rhodanese modules are versatile sulfur carriers that have adapted their function to fulfill the need for reactive sulfane sulfur in distinct metabolic and regulatory pathways. Recent investigations have shown that rhodanese domains are also structurally related to the catalytic subunit of Cdc25 phosphatase enzymes and that the two enzyme families are likely to share a common evolutionary origin. In this review, the rhodanese/Cdc25 phosphatase superfamily is analyzed. Although the identification of their biological substrates has thus far proven elusive, the emerging picture points to a role for the amino-acid composition of the active-site loop in substrate recognition/specificity. Furthermore, the frequently observed association of catalytically inactive rhodanese modules with other protein domains suggests a distinct regulatory role for these inactive domains, possibly in connection with signaling.
238.
Comparative analysis of protein interaction networks.
Bork P
2002; 18 Suppl 2: S64. PubMed: 12385984.
Abstract + PDFRecent advances in proteomics and computational biology have lead to a flood of protein interaction data and resulting interaction networks (e.g. (Gavin et al., 2002)). Here I first analyse the status and quality of parts lists (genes and proteins), then comparatively assess large-scale protein interaction data (von Mering et al., 2002) and finally try to identify biological meaningful units (e.g. pathways, cellular processes) within interaction networks that are derived from the conservation of gene neighborhood (Snel et al., 2002). Possible extensions of gene neighborhood analysis to eukaryotes (von Mering and Bork, 2002) will be discussed.
237.
Alternative splicing and genome complexity.
Brett D, Pospisil H, Valcárcel J, Reich J, Bork P
Abstract + PDFAlternative splicing of mRNA allows many gene products with different functions to be produced from a single coding sequence. It has recently been proposed as a mechanism by which higher-order diversity is generated. Here we show, using large-scale expressed sequence tag (EST) analysis, that among seven different eukaryotes the amount of alternative splicing is comparable, with no large differences between humans and other animals.
236.
Immunity-related genes and gene families in Anopheles gambiae.
Christophides GK, Zdobnov EM, Barillas-Mury C, Birney E, Blandin S, Blass C, Brey PT, Collins FH, Danielli A, Dimopoulos G, Hetru C, Hoa NT, Hoffmann JA, Kanzok SM, Letunic I, Levashina EA, Loukeris TG, Lycett G, Meister S, Michel K, Moita LF, Müller HM, Osta MA, Paskewitz SM, Reichhart JM, Rzhetsky A, Troxler L, Vernick KD, Vlachou D, Volz J, von Mering C, Xu J, Zheng L, Bork P, Kafatos FC
Abstract + PDFWe have identified 242 Anopheles gambiae genes from 18 gene families implicated in innate immunity and have detected marked diversification relative to Drosophila melanogaster. Immune-related gene families involved in recognition, signal modulation, and effector systems show a marked deficit of orthologs and excessive gene expansions, possibly reflecting selection pressures from different pathogens encountered in these insects' very different life-styles. In contrast, the multifunctional Toll signal transduction pathway is substantially conserved, presumably because of counterselection for developmental stability. Representative expression profiles confirm that sequence diversification is accompanied by specific responses to different immune challenges. Alternative RNA splicing may also contribute to expansion of the immune repertoire.
235.
CASH--a beta-helix domain widespread among carbohydrate-binding proteins.
2002 Feb; 27(2): 59-62. PubMed: 11852237.
Abstract + PDFIn this article, we describe a novel, widespread domain (CASH) that is shared by many carbohydrate-binding proteins and sugar hydrolases. This domain occurs in more than 1000 proteins distributed among all three kingdoms of life. The CASH domain is characterized by internal repetitions of glycines and hydrophobic residues that correspond to the repetitive units of a predicted or observed right-handed beta-helix structure of the pectate lyase superfamily.
234.
AMOP, a protein module alternatively spliced in cancer cells.
2002 Mar; 27(3): 113-5. PubMed: 11893501.
Abstract + PDFThis article describes a new extracellular domain--AMOP, for adhesion-associated domain in MUC4 and other proteins. This domain occurs in putative cell adhesion molecules and in some splice variants of MUC4. MUC4 splice variants are overexpressed in several tumours; in particular, they are highly expressed in pancreatic carcinomas but not in normal pancreas. The presence of AMOP in cell adhesion molecules could be indicative of a role for this domain in adhesion.
233.
Protein domain analysis in the era of complete genomes.
Abstract + PDFDomains present one of the most useful levels at which to understand protein function, and domain family-based analysis has had a profound impact on the study of individual proteins. Protein domain discovery has been progressing steadily over the past 30 years. What are the realistically achievable goals of sequence-based domain analysis, and how far off are they for the sequences encoded in eukaryotic genomes? Here we address some of the issues involved in better coverage of sequence-based domain annotation, and the integration of these results within the wider context of genomes, structures and function.
232.
Genome and protein evolution in eukaryotes.
2002 Feb; 6(1): 39-45. PubMed: 11827821.
Abstract + PDFThe past year has seen the completion of the genome sequence of the flowering plant Arabidopsis thaliana and the initial sequence reports of the human genome. The availability of completely sequenced eukaryotic genomes from disparate phylogenetic lineages has opened the door to comparative analyses and a better understanding of the evolutionary processes shaping genomes. Complex many-to-many relationships between genes from different species appear to be the norm, suggesting that transfer of detailed functional annotation will not be straightforward. In addition to expansion and contraction of gene families, new genes evolve from recombination of pre-existing domains, although some domain families do appear to have evolved recently and to be specific to restricted phylogenetic lineages. The overall picture is of a huge diversity of gene content within eukaryotic genomes, reflecting different functional demands in different species.
231.
Sequence analysis of multidomain proteins: past perspectives and future directions.
2002; 61: 75-98. PubMed: 12461821.
PDF230.
Comparative Genome Analysis of the Mollicutes.
In: Molecular Biology and Pathogenicity of Mycoplasmas. (Razin and Herrmann, eds.) pp.255-278. BID: 5.
Publisher: Kluwer Academic/Plenum Publishers, New York
PDF229.
Systematic identification of novel protein domain families associated with nuclear functions.
2002 Jan; 12(1): 47-56. PubMed: 11779830.
Abstract + PDFA systematic computational analysis of protein sequences containing known nuclear domains led to the identification of 28 novel domain families. This represents a 26% increase in the starting set of 107 known nuclear domain families used for the analysis. Most of the novel domains are present in all major eukaryotic lineages, but 3 are species specific. For about 500 of the 1200 proteins that contain these new domains, nuclear localization could be inferred, and for 700, additional features could be predicted. For example, we identified a new domain, likely to have a role downstream of the unfolded protein response; a nematode-specific signalling domain; and a widespread domain, likely to be a noncatalytic homolog of ubiquitin-conjugating enzymes.
228.
BSD: a novel domain in transcription factors and synapse-associated proteins.
Doerks T, Huber S, Buchner E, Bork P
2002 Apr; 27(4): 168-70. PubMed: 11943536.
Abstract + PDFThis article describes a novel domain, BSD, that is present in basal transcription factors, synapse-associated proteins and several hypothetical proteins. It occurs in a variety of species ranging from primal protozoan to human. The BSD domain is characterized by three predicted alpha helices, which probably form a three-helical bundle, as well as by conserved tryptophan and phenylalanine residues, located at the C terminus of the domain.
227.
HGVbase: a human sequence variation database emphasizing data quality and a broad spectrum of data sources.
Fredman D, Siegfried M, Yuan YP, Bork P, Lehväslaiho H, Brookes AJ
2002 Jan 1; 30(1): 387-91. PubMed: 11752345.
Abstract + PDFHGVbase (Human Genome Variation database; http://hgvbase.cgb.ki.se, formerly known as HGBASE) is an academic effort to provide a high quality and non-redundant database of available genomic variation data of all types, mostly comprising single nucleotide polymorphisms (SNPs). Records include neutral polymorphisms as well as disease-related mutations. Online search tools facilitate data interrogation by sequence similarity and keyword queries, and searching by genome coordinates is now being implemented. Downloads are freely available in XML, Fasta, SRS, SQL and tagged-text file formats. Each entry is presented in the context of its surrounding sequence and many records are related to neighboring human genes and affected features therein. Population allele frequencies are included wherever available. Thorough semi-automated data checking ensures internal consistency and addresses common errors in the source information. To keep pace with recent growth in the field, we have developed tools for fully automated annotation. All variants have been uniquely mapped to the draft genome sequence and are referenced to positions in EMBL/GenBank files. Data utility is enhanced by provision of genotyping assays and functional predictions. Recent data structure extensions allow the capture of haplotype and genotype information, and a new initiative (along with BiSC and HUGO-MDI) aims to create a central repository for the broad collection of clinical mutations and associated disease phenotypes of interest.
226.
Functional organization of the yeast proteome by systematic analysis of protein complexes.
Gavin AC, Bösche M, Krause R, Grandi P, Marzioch M, Bauer A, Schultz J, Rick JM, Michon AM, Cruciat CM, Remor M, Höfert C, Schelder M, Brajenovic M, Ruffner H, Merino A, Klein K, Hudak M, Dickson D, Rudi T, Gnau V, Bauch A, Bastuck S, Huhse B, Leutwein C, Heurtier MA, Copley RR, Edelmann A, Querfurth E, Rybin V, Drewes G, Raida M, Bouwmeester T, Bork P, Seraphin B, Kuster B, Neubauer G, Superti-Furga G
Abstract + PDFMost cellular processes are carried out by multiprotein complexes. The identification and analysis of their components provides insight into how the ensemble of expressed proteins (proteome) is organized into functional units. We used tandem-affinity purification (TAP) and mass spectrometry in a large-scale approach to characterize multiprotein complexes in Saccharomyces cerevisiae. We processed 1,739 genes, including 1,143 human orthologues of relevance to human biology, and purified 589 protein assemblies. Bioinformatic analysis of these assemblies defined 232 distinct multiprotein complexes and proposed new cellular roles for 344 proteins, including 231 proteins with no previous functional annotation. Comparison of yeast and human complexes showed that conservation across species extends from single proteins to their molecular environment. Our analysis provides an outline of the eukaryotic proteome as a network of protein complexes at a level of organization beyond binary interactions. This higher-order map contains fundamental biological information and offers the context for a more reasoned and informed approach to drug discovery.
225.
The genome sequence of the malaria mosquito Anopheles gambiae.
Holt RA, Subramanian GM, Halpern A, Sutton GG, Charlab R, Nusskern DR, Wincker P, Clark AG, Ribeiro JM, Wides R, Salzberg SL, Loftus B, Yandell M, Majoros WH, Rusch DB, Lai Z, Kraft CL, Abril JF, Anthouard V, Arensburger P, Atkinson PW, Baden H, de Berardinis V, Baldwin D, Benes V, Biedler J, Blass C, Bolanos R, Boscus D, Barnstead M, Cai S, Center A, Chaturverdi K, Christophides GK, Chrystal MA, Clamp M, Cravchik A, Curwen V, Dana A, Delcher A, Dew I, Evans CA, Flanigan M, Grundschober-Freimoser A, Friedli L, Gu Z, Guan P, Guigo R, Hillenmeyer ME, Hladun SL, Hogan JR, Hong YS, Hoover J, Jaillon O, Ke Z, Kodira C, Kokoza E, Koutsos A, Letunic I, Levitsky A, Liang Y, Lin JJ, Lobo NF, Lopez JR, Malek JA, McIntosh TC, Meister S, Miller J, Mobarry C, Mongin E, Murphy SD, O'Brochta DA, Pfannkoch C, Qi R, Regier MA, Remington K, Shao H, Sharakhova MV, Sitter CD, Shetty J, Smith TJ, Strong R, Sun J, Thomasova D, Ton LQ, Topalis P, Tu Z, Unger MF, Walenz B, Wang A, Wang J, Wang M, Wang X, Woodford KJ, Wortman JR, Wu M, Yao A, Zdobnov EM, Zhang H, Zhao Q, Zhao S, Zhu SC, Zhimulev I, Coluzzi M, della Torre A, Roth CW, Louis C, Kalush F, Mural RJ, Myers EW, Adams MD, Smith HO, Broder S, Gardner MJ, Fraser CM, Birney E, Bork P, Brey PT, Venter JC, Weissenbach J, Kafatos FC, Collins FH, Hoffman SL
Abstract + PDFAnopheles gambiae is the principal vector of malaria, a disease that afflicts more than 500 million people and causes more than 1 million deaths each year. Tenfold shotgun sequence coverage was obtained from the PEST strain of A. gambiae and assembled into scaffolds that span 278 million base pairs. A total of 91% of the genome was organized in 303 scaffolds; the largest scaffold was 23.1 million base pairs. There was substantial genetic variation within this strain, and the apparent existence of two haplotypes of approximately equal frequency ("dual haplotypes") in a substantial fraction of the genome likely reflects the outbred nature of the PEST strain. The sequence produced a conservative inference of more than 400,000 single-nucleotide polymorphisms that showed a markedly bimodal density distribution. Analysis of the genome sequence revealed strong evidence for about 14,000 protein-encoding transcripts. Prominent expansions in specific families of proteins likely involved in cell adhesion and immunity were noted. An expressed sequence tag analysis of genes regulated by blood feeding provided insights into the physiological adaptations of a hematophagous insect.
224.
Identification and characterization of UEV3, a human cDNA with similarities to inactive E2 ubiquitin-conjugating enzymes.
Kloor M, Bork P, Duwe A, Klaes R, von Knebel Doeberitz M, Ridder R
2002 Dec 12; 1579(2-3): 219-24. PubMed: 12427560.
Abstract + PDFRecent studies have shown that ubiquitination is an essential factor in endosomal sorting and virus assembly. The human TSG101 gene has been demonstrated to belong to a group of genes coding for apparently inactive E2 ubiquitin-conjugating enzymes, which exert regulatory effects on E2 activity in cellular ubiquitination processes. In this study, a novel human cDNA (UEV3) encoding a putative protein of 379 amino acids was isolated from a human placenta library that may represent a partial paralogue of human TSG101. The predicted protein contains an N-terminal domain homologous to the catalytic domain of ubiquitin-conjugating enzymes (Ubc), which is fused to a sequence showing significant homology to members of the lactate dehydrogenase protein family. The UEV3 gene is located on chromosome 11 closely adjacent to TSG101 and LDH-C. Northern blot and UEV3-specific reverse transcription/polymerase chain reaction (RT/PCR) analyses of various colon carcinoma cell lines as well as both normal and tumor samples from colon revealed an expression of the UEV3 cDNA in all tested samples.
223.
SHOT: a web server for the construction of genome phylogenies.
2002 Mar; 18(3): 158-62. PubMed: 11858840.
Abstract + PDFWith the increasing availability of genome sequences, new methods are being proposed that exploit information from complete genomes to classify species in a phylogeny. Here we present SHOT, a web server for the classification of genomes on the basis of shared gene content or the conservation of gene order that reflects the dominant, phylogenetic signal in these genomic properties. In general, the genome trees are consistent with classical gene-based phylogenies, although some interesting exceptions indicate massive horizontal gene transfer. SHOT is a useful tool for analysing the tree of life from a genomic point of view. It is available at http://www.Bork.EMBL-Heidelberg.de/SHOT.
222.
Common exon duplication in animals and its role in alternative splicing.
2002 Jun 15; 11(13): 1561-7. PubMed: 12045209.
Abstract + PDFWhen searching the genomes of human, fly and worm for cases of exon duplication, we found that about 10% of all genes contain tandemly duplicated exons. In the course of the analyses, 2438 unannotated exons were identified that are not currently included in genome databases and that are likely to be functional. The vast majority of them are likely to be involved in mutually exclusive alternative splicing events. The common nature of recent exon duplication indicates that it might have a significant role in the fast evolution of eukaryotic genes. It also provides a general mechanism for the regulation of protein function.
221.
Recent improvements to the SMART domain-based sequence annotation resource.
Letunic I, Goodstadt L, Dickens NJ, Doerks T, Schultz J, Mott R, Ciccarelli F, Copley RR, Ponting CP, Bork P
2002 Jan 1; 30(1): 242-4. PubMed: 11752305.
Abstract + PDFSMART (Simple Modular Architecture Research Tool, http://smart.embl-heidelberg.de) is a web-based resource used for the annotation of protein domains and the analysis of domain architectures, with particular emphasis on mobile eukaryotic domains. Extensive annotation for each domain family is available, providing information relating to function, subcellular localization, phyletic distribution and tertiary structure. The January 2002 release has added more than 200 hand-curated domain models. This brings the total to over 600 domain families that are widely represented among nuclear, signalling and extracellular proteins. Annotation now includes links to the Online Mendelian Inheritance in Man (OMIM) database in cases where a human disease is associated with one or more mutations in a particular domain. We have implemented new analysis methods and updated others. New advanced queries provide direct access to the SMART relational database using SQL. This database now contains information on intrinsic sequence features such as transmembrane regions, coiled-coils, signal peptides and internal repeats. SMART output can now be easily included in users' documents. A SMART mirror has been created at http://smart.ox.ac.uk.
220.
Predicting protein cellular localization using a domain projection method.
Mott R, Schultz J, Bork P, Ponting CP
2002 Aug; 12(8): 1168-74. PubMed: 12176924.
Abstract + PDFWe investigate the co-occurrence of domain families in eukaryotic proteins to predict protein cellular localization. Approximately half (300) of SMART domains form a "small-world network", linked by no more than seven degrees of separation. Projection of the domains onto two-dimensional space reveals three clusters that correspond to cellular compartments containing secreted, cytoplasmic, and nuclear proteins. The projection method takes into account the existence of "bridging" domains, that is, instances where two domains might not occur with each other but frequently co-occur with a third domain; in such circumstances the domains are neighbors in the projection. While the majority of domains are specific to a compartment ("locale"), and hence may be used to localize any protein that contains such a domain, a small subset of domains either are present in multiple locales or occur in transmembrane proteins. Comparison with previously annotated proteins shows that SMART domain data used with this approach can predict, with 92% accuracy, the localizations of 23% of eukaryotic proteins. The coverage and accuracy will increase with improvements in domain database coverage. This method is complementary to approaches that use amino-acid composition or identify sorting sequences; these methods may be combined to further enhance prediction accuracy.
219.
InterPro: an integrated documentation resource for protein families, domains and functional sites.
Mulder NJ, Apweiler R, Attwood TK, Bairoch A, Bateman A, Binns D, Biswas M, Bradley P, Bork P, Bucher P, Copley R, Courcelle E, Durbin R, Falquet L, Fleischmann W, Gouzy J, Griffith-Jones S, Haft D, Hermjakob H, Hulo N, Kahn D, Kanapin A, Krestyaninova M, Lopez R, Letunic I, Orchard S, Pagni M, Peyruc D, Ponting CP, Servant F, Sigrist CJ, InterPro Consortium
2002 Sep; 3(3): 225-35. PubMed: 12230031.
Abstract + PDFThe exponential increase in the submission of nucleotide sequences to the nucleotide sequence database by genome sequencing centres has resulted in a need for rapid, automatic methods for classification of the resulting protein sequences. There are several signature and sequence cluster-based methods for protein classification, each resource having distinct areas of optimum application owing to the differences in the underlying analysis methods. In recognition of this, InterPro was developed as an integrated documentation resource for protein families, domains and functional sites, to rationalise the complementary efforts of the individual protein signature database projects. The member databases - PRINTS, PROSITE, Pfam, ProDom, SMART and TIGRFAMs - form the InterPro core. Related signatures from each member database are unified into single InterPro entries. Each InterPro entry includes a unique accession number, functional descriptions and literature references, and links are made back to the relevant member database(s). Release 4.0 of InterPro (November 2001) contains 4,691 entries, representing 3,532 families, 1,068 domains, 74 repeats and 15 sites of post-translational modification (PTMs) encoded by different regular expressions, profiles, fingerprints and hidden Markov models (HMMs). Each InterPro entry lists all the matches against SWISS-PROT and TrEMBL (2,141,621 InterPro hits from 586,124 SWISS-PROT and TrEMBL protein sequences). The database is freely accessible for text- and sequence-based searches.
218.
SPG20 is mutated in Troyer syndrome, an hereditary spastic paraplegia.
Patel H, Cross H, Proukakis C, Hershberger R, Bork P, Ciccarelli FD, Patton MA, McKusick VA, Crosby AH
Abstract + PDFTroyer syndrome (TRS) is an autosomal recessive complicated hereditary spastic paraplegia (HSP) that occurs with high frequency in the Old Order Amish. We report mapping of the TRS locus to chromosome 13q12.3 and identify a frameshift mutation in SPG20, encoding spartin. Comparative sequence analysis indicates that spartin shares similarity with molecules involved in endosomal trafficking and with spastin, a molecule implicated in microtubule interaction that is commonly mutated in HSP.
217.
Exploring MEDLINE abstracts with XplorMed.
2002 Jun; 38(6): 381-9. PubMed: 12532176.
AbstractXplorMed is a publicly available web tool conceived to make life easier for MEDLINE(c) users looking for scientific information. Searching scientific literature is an information retrieval problem. Abstracts that are of possible interest to the user are usually selected by a keyword search followed by manual screening, which often results in the retrieval of a large number of abstracts. Interesting references can be buried among irrelevant ones because of nonspecific queries. XplorMed is intended to extract dependency relations between the words of the abstracts. These relations can be filtered and arranged to deduce different subjects in the query and offer a condensed view of the abstract, allowing users to select texts of interest without having to read them all. XplorMed is available http://www.bork. embl-heidelberg.de/xplormed.
216.
Association of genes to genetically inherited diseases using data mining.
Abstract + PDFAlthough approximately one-quarter of the roughly 4,000 genetically inherited diseases currently recorded in respective databases (LocusLink, OMIM) are already linked to a region of the human genome, about 450 have no known associated gene. Finding disease-related genes requires laborious examination of hundreds of possible candidate genes (sometimes, these are not even annotated; see, for example, refs 3,4). The public availability of the human genome draft sequence has fostered new strategies to map molecular functional features of gene products to complex phenotypic descriptions, such as those of genetically inherited diseases. Owing to recent progress in the systematic annotation of genes using controlled vocabularies, we have developed a scoring system for the possible functional relationships of human genes to 455 genetically inherited diseases that have been mapped to chromosomal regions without assignment of a particular gene. In a benchmark of the system with 100 known disease-associated genes, the disease-associated gene was among the 8 best-scoring genes with a 25% chance, and among the best 30 genes with a 50% chance, showing that there is a relationship between the score of a gene and its likelihood of being associated with a particular disease. The scoring also indicates that for some diseases, the chance of identifying the underlying gene is higher.
215.
Computing fuzzy associations for the analysis of biological literature.
2002 Jun; 32(6): 1380-2, 1384-5. PubMed: 12074170.
Abstract + PDFThe increase of information in biology makes it difficult for researchers in any field to keep current with the literature. The MEDLINE database of scientific abstracts can be quickly scanned using electronic mechanisms. Potentially interesting abstracts can be selected by matching words joined by Boolean operators. However this means of selecting documents is not optimal. Nonspecific queries have to be effected, resulting in large numbers of irrelevant abstracts that have to be manually scanned To facilitate this analysis, we have developed a system that compiles a summary of subjects and related documents on the results of a MEDLINE query. For this, we have applied a fuzzy binary relation formalism that deduces relations between words present in a set of abstracts preprocessed with a standard grammatical tagger. Those relations are used to derive ensembles of related words and their associated subsets of abstracts. The algorithm can be used publicly at http:// www.bork.embl-heidelberg.de/xplormed/.
214.
Human non-synonymous SNPs: server and survey.
2002 Sep 1; 30(17): 3894-900. PubMed: 12202775.
Abstract + PDFHuman single nucleotide polymorphisms (SNPs) represent the most frequent type of human population DNA variation. One of the main goals of SNP research is to understand the genetics of the human phenotype variation and especially the genetic basis of human complex diseases. Non-synonymous coding SNPs (nsSNPs) comprise a group of SNPs that, together with SNPs in regulatory regions, are believed to have the highest impact on phenotype. Here we present a World Wide Web server to predict the effect of an nsSNP on protein structure and function. The prediction method enabled analysis of the publicly available SNP database HGVbase, which gave rise to a dataset of nsSNPs with predicted functionality. The dataset was further used to compare the effect of various structural and functional characteristics of amino acid substitutions responsible for phenotypic display of nsSNPs. We also studied the dependence of selective pressure on the structural and functional properties of proteins. We found that in our dataset the selection pressure against deleterious SNPs depends on the molecular function of the protein, although it is insensitive to several other protein features considered. The strongest selective pressure was detected for proteins involved in transcription regulation.
213.
The genome sequence of Bifidobacterium longum reflects its adaptation to the human gastrointestinal tract.
Schell MA, Karmirantzou M, Snel B, Vilanova D, Berger B, Pessi G, Zwahlen MC, Desiere F, Bork P, Delley M, Pridmore RD, Arigoni F
2002 Oct 29; 99(22): 14422-7. Epub 2002 Oct 15; PubMed: 12381787.
Abstract + PDFBifidobacteria are Gram-positive prokaryotes that naturally colonize the human gastrointestinal tract (GIT) and vagina. Although not numerically dominant in the complex intestinal microflora, they are considered as key commensals that promote a healthy GIT. We determined the 2.26-Mb genome sequence of an infant-derived strain of Bifidobacterium longum, and identified 1,730 possible coding sequences organized in a 60%-GC circular chromosome. Bioinformatic analysis revealed several physiological traits that could partially explain the successful adaptation of this bacteria to the colon. An unexpectedly large number of the predicted proteins appeared to be specialized for catabolism of a variety of oligosaccharides, some possibly released by rare or novel glycosyl hydrolases acting on "nondigestible" plant polymers or host-derived glycoproteins and glycoconjugates. This ability to scavenge from a large variety of nutrients likely contributes to the competitiveness and persistence of bifidobacteria in the colon. Many genes for oligosaccharide metabolism were found in self-regulated modules that appear to have arisen in part from gene duplication or horizontal acquisition. Complete pathways for all amino acids, nucleotides, and some key vitamins were identified; however, routes for Asp and Cys were atypical. More importantly, genome analysis provided insights into the reciprocal interactions of bifidobacteria with their hosts. We identified polypeptides that showed homology to most major proteins needed for production of glycoprotein-binding fimbriae, structures that could possibly be important for adhesion and persistence in the GIT. We also found a eukaryotic-type serine protease inhibitor (serpin) possibly involved in the reported immunomodulatory activity of bifidobacteria.
212.
A versatile structural domain analysis server using profile weight matrices.
2002 Mar-Apr; 42(2): 405-7. PubMed: 11911710.
Abstract + PDFThe WEB tool "AnDom" assigns to a given protein sequence all experimentally determined structural domains contained within it, including multidomain and large proteins. The server uses profile specific matrices from custom generated multiple sequence alignments of all known SCOP domains (SCOP version 1.50). Prediction time is short allowing numerous applications for structural genomics including investigation of complex eucaryotic protein families. The WWW server is at http://www.bork.embl-heidelberg.de/AnDom, and profiles can be downloaded at ftp.bork.embl-heidelberg.de/pub/users/schmidt/AnDom.
211.
Conservation of gene co-regulation in prokaryotes and eukaryotes.
2002 Oct 1; 20(10): 410. PID: 338.
Abstract + PDFWe raise some issues in detecting the conservation (or absence thereof) of co-regulation using gene order; how we think the variations in the cellular network in various species can be studied; and how to determine and interpret the higher order structure in networks of functional relations.
210.
The identification of functional modules from the genomic association of genes.
2002 Apr 30; 99(9): 5890-5. PubMed: 11983890.
Abstract + PDFBy combining the pairwise interactions between proteins, as predicted by the conserved co-occurrence of their genes in operons, we obtain protein interaction networks. Here we study the properties of such networks to identify functional modules: sets of proteins that together are involved in a biological process. The complete network contains 3,033 orthologous groups of proteins in 38 genomes. It consists of one giant component, containing 1,611 orthologous groups, and of 516 small disjointed clusters that, on average, contain only 2.7 orthologous groups. These small clusters have a homogeneous functional composition and thus represent functional modules in themselves. Analysis of the giant component reveals that it is a scale-free, small-world network with a high degree of local clustering (C = 0.6). It consists of locally highly connected subclusters that are connected to each other by linker proteins. The linker proteins tend to have multiple functions, or are involved in multiple processes and have an above average probability of being essential. By splitting up the giant component at these linker proteins, we identify 265 subclusters that tend to have a homogeneous functional composition. The rare functional inhomogeneities in our subclusters reflect the mixing of different types of (molecular) functions in a single cellular process, exemplified by subclusters containing both metabolic enzymes as well as the transcription factors that regulate them. Comparative genome analysis, thus, allows identification of a level of functional interaction between that of pairwise interactions, and of the complete genome.
209.
Genomes in flux: the evolution of archaeal and proteobacterial gene content.
2002 Jan; 12(1): 17-25. PubMed: 11779827.
Abstract + PDFIn the course of evolution, genomes are shaped by processes like gene loss, gene duplication, horizontal gene transfer, and gene genesis (the de novo origin of genes). Here we reconstruct the gene content of ancestral Archaea and Proteobacteria and quantify the processes connecting them to their present day representatives based on the distribution of genes in completely sequenced genomes. We estimate that the ancestor of the Proteobacteria contained around 2500 genes, and the ancestor of the Archaea around 2050 genes. Although it is necessary to invoke horizontal gene transfer to explain the content of present day genomes, gene loss, gene genesis, and simple vertical inheritance are quantitatively the most dominant processes in shaping the genome. Together they result in a turnover of gene content such that even the lineage leading from the ancestor of the Proteobacteria to the relatively large genome of Escherichia coli has lost at least 950 genes. Gene loss, unlike the other processes, correlates fairly well with time. This clock-like behavior suggests that gene loss is under negative selection, while the processes that add genes are under positive selection.
208.
Comparative genomic analysis in the region of a major Plasmodium-refractoriness locus of Anopheles gambiae.
2002 Jun 11; 99(12): 8179-84. PubMed: 12060762.
Abstract + PDFWe have sequenced six overlapping clones from a library of bacterial artificial chromosome (BAC) clones derived from a laboratory strain of the mosquito, Anopheles gambiae, the major vector of human malaria in Africa. The resulting uninterrupted 528-kb sequence is from the 8C region of the mosquito 2R chromosome, at or very near the major refractoriness locus associated with melanotic encapsulation of parasites. This sequence represents the first extensive view of the mosquito genome structure encompassing 48 genes. Genomic comparison reveals that the majority of the orthologues are found in six microsyntenic clusters in Drosophila melanogaster. A BAC clone that is wholly contained within this region demonstrates the existence of a remarkable degree of local polymorphism in this species, which may prove important for its population structure and vectorial capacity.
207.
Proteinkomplexe und Netzwerke: Neue Herausforderungen für die Proteomik.
von Mering C, Bork P
2002; 2: 2-4. PID: 310.
PDF205.
Comparative assessment of large-scale data sets of protein-protein interactions.
Abstract + PDFComprehensive protein protein interaction maps promise to reveal many aspects of the complex regulatory network underlying cellular function. Recently, large-scale approaches have predicted many new protein interactions in yeast. To measure their accuracy and potential as well as to identify biases, strengths and weaknesses, we compare the methods with each other and with a reference set of previously reported protein interactions.
204.
Initial sequencing and comparative analysis of the mouse genome.
Waterston RH, Lindblad-Toh K, Birney E, Rogers J, Abril JF, Agarwal P, Agarwala R, Ainscough R, Alexandersson M, An P, Antonarakis SE, Attwood J, Baertsch R, Bailey J, Barlow K, Beck S, Berry E, Birren B, Bloom T, Bork P, Botcherby M, Bray N, Brent MR, Brown DG, Brown SD, Bult C, Burton J, Butler J, Campbell RD, Carninci P, Cawley S, Chiaromonte F, Chinwalla AT, Church DM, Clamp M, Clee C, Collins FS, Cook LL, Copley RR, Coulson A, Couronne O, Cuff J, Curwen V, Cutts T, Daly M, David R, Davies J, Delehaunty KD, Deri J, Dermitzakis ET, Dewey C, Dickens NJ, Diekhans M, Dodge S, Dubchak I, Dunn DM, Eddy SR, Elnitski L, Emes RD, Eswara P, Eyras E, Felsenfeld A, Fewell GA, Flicek P, Foley K, Frankel WN, Fulton LA, Fulton RS, Furey TS, Gage D, Gibbs RA, Glusman G, Gnerre S, Goldman N, Goodstadt L, Grafham D, Graves TA, Green ED, Gregory S, Guigó R, Guyer M, Hardison RC, Haussler D, Hayashizaki Y, Hillier LW, Hinrichs A, Hlavina W, Holzer T, Hsu F, Hua A, Hubbard T, Hunt A, Jackson I, Jaffe DB, Johnson LS, Jones M, Jones TA, Joy A, Kamal M, Karlsson EK, Karolchik D, Kasprzyk A, Kawai J, Keibler E, Kells C, Kent WJ, Kirby A, Kolbe DL, Korf I, Kucherlapati RS, Kulbokas EJ, Kulp D, Landers T, Leger JP, Leonard S, Letunic I, Levine R, Li J, Li M, Lloyd C, Lucas S, Ma B, Maglott DR, Mardis ER, Matthews L, Mauceli E, Mayer JH, McCarthy M, McCombie WR, McLaren S, McLay K, McPherson JD, Meldrim J, Meredith B, Mesirov JP, Miller W, Miner TL, Mongin E, Montgomery KT, Morgan M, Mott R, Mullikin JC, Muzny DM, Nash WE, Nelson JO, Nhan MN, Nicol R, Ning Z, Nusbaum C, O'Connor MJ, Okazaki Y, Oliver K, Overton-Larty E, Pachter L, Parra G, Pepin KH, Peterson J, Pevzner P, Plumb R, Pohl CS, Poliakov A, Ponce TC, Ponting CP, Potter S, Quail M, Reymond A, Roe BA, Roskin KM, Rubin EM, Rust AG, Santos R, Sapojnikov V, Schultz B, Schultz J, Schwartz MS, Schwartz S, Scott C, Seaman S, Searle S, Sharpe T, Sheridan A, Shownkeen R, Sims S, Singer JB, Slater G, Smit A, Smith DR, Spencer B, Stabenau A, Stange-Thomann N, Sugnet C, Suyama M, Tesler G, Thompson J, Torrents D, Trevaskis E, Tromp J, Ucla C, Ureta-Vidal A, Vinson JP, Von Niederhausern AC, Wade CM, Wall M, Weber RJ, Weiss RB, Wendl MC, West AP, Wetterstrand K, Wheeler R, Whelan S, Wierzbowski J, Willey D, Williams S, Wilson RK, Winter E, Worley KC, Wyman D, Yang S, Yang SP, Zdobnov EM, Zody MC, Lander ES, Mouse Genome Sequencing Consortium
Abstract + PDFThe sequence of the mouse genome is a key informational tool for understanding the contents of the human genome and a key experimental tool for biomedical research. Here, we report the results of an international collaboration to produce a high-quality draft sequence of the mouse genome. We also present an initial comparative analysis of the mouse and human genomes, describing some of the insights that can be gleaned from the two sequences. We discuss topics including the analysis of the evolutionary forces shaping the size, structure and sequence of the genomes; the conservation of large-scale synteny across most of the genomes; the much lower extent of sequence orthology covering less than half of the genomes; the proportions of the genomes under selection; the number of protein-coding genes; the expansion of gene families related to reproduction and immunity; the evolution of proteins; and the identification of intraspecies polymorphism.
203.
Comparative genome and proteome analysis of Anopheles gambiae and Drosophila melanogaster.
Zdobnov EM, von Mering C, Letunic I, Torrents D, Suyama M, Copley RR, Christophides GK, Thomasova D, Holt RA, Subramanian GM, Mueller HM, Dimopoulos G, Law JH, Wells MA, Birney E, Charlab R, Halpern AL, Kokoza E, Kraft CL, Lai Z, Lewis S, Louis C, Barillas-Mury C, Nusskern D, Rubin GM, Salzberg SL, Sutton GG, Topalis P, Wides R, Wincker P, Yandell M, Collins FH, Ribeiro J, Gelbart WM, Kafatos FC, Bork P
Abstract + PDFComparison of the genomes and proteomes of the two diptera Anopheles gambiae and Drosophila melanogaster, which diverged about 250 million years ago, reveals considerable similarities. However, numerous differences are also observed; some of these must reflect the selection and subsequent adaptation associated with different ecologies and life strategies. Almost half of the genes in both genomes are interpreted as orthologs and show an average sequence identity of about 56%, which is slightly lower than that observed between the orthologs of the pufferfish and human (diverged about 450 million years ago). This indicates that these two insects diverged considerably faster than vertebrates. Aligned sequences reveal that orthologous genes have retained only half of their intron/exon structure, indicating that intron gains or losses have occurred at a rate of about one per gene per 125 million years. Chromosomal arms exhibit significant remnants of homology between the two species, although only 34% of the genes colocalize in small "microsyntenic" clusters, and major interarm transfers as well as intra-arm shuffling of gene order are detected.
2001 21 publication(s).
202.
Comparison of ARM and HEAT protein repeats.
Andrade MA, Petosa C, O'Donoghue SI, Müller CW, Bork P
2001 May 25; 309(1): 1-18. PubMed: 11491282.
Abstract + PDFARM and HEAT motifs are tandemly repeated sequences of approximately 50 amino acid residues that occur in a wide variety of eukaryotic proteins. An exhaustive search of sequence databases detected new family members and revealed that at least 1 in 500 eukaryotic protein sequences contain such repeats. It also rendered the similarity between ARM and HEAT repeats, believed to be evolutionarily related, readily apparent. All the proteins identified in the database searches could be clustered by sequence similarity into four groups: canonical ARM-repeat proteins and three groups of the more divergent HEAT-repeat proteins. This allowed us to build improved sequence profiles for the automatic detection of repeat motifs. Inspection of these profiles indicated that the individual repeat motifs of all four classes share a common set of seven highly conserved hydrophobic residues, which in proteins of known three-dimensional structure are buried within or between repeats. However, the motifs differ at several specific residue positions, suggesting important structural or functional differences among the classes. Our results illustrate that ARM and HEAT-repeat proteins, while having a common phylogenetic origin, have since diverged significantly. We discuss evolutionary scenarios that could account for the great diversity of repeats observed.
201.
The black-pearl gene of Drosophila defines a novel conserved protein family and is required for larval growth and survival.
Becker S, Gehrsitz A, Bork P, Buchner S, Buchner E
Abstract + PDFUsing a transposon insertion line of the Drosophila Genome Project we have cloned the black-pearl gene (blp), analyzed cDNA clones, generated various mutants, and characterized their phenotypes. The blp gene codes for a protein of 15.7 kDa calculated molecular weight that has been conserved from yeast to plants and mammals with high homology. A domain of these new proteins shows distant similarity to DnaJ domains indicating a functionally relevant interaction with other proteins. The P element insertion in line P1539 lies within the 5' untranslated leader of the black-pearl gene. Flies homozygous for this insertion are semi-lethal, escapers produce very few offspring and show melanotic inclusions in the hemocoel ('black pearls') similar to various melanotic 'tumor' mutants. Two small deletions confined to the blp gene and two EMS-induced mutations are homozygous lethal. These null mutants appear normal up to a prolonged first instar larval stage but fail to grow and die. Thus in Drosophila the blp gene is specifically required for larval growth. The evolutionary conservation in both unicellular and multicellular organisms suggests for the new protein family described here a fundamental role in cell growth.
198.
DDT -- a novel domain in different transcription and chromosome remodeling factors.
Doerks T, Copley R, Bork P
2001 Mar; 26(3): 145-6. PubMed: 11246006.
Abstract + PDFHomology-based sequence analyses have revealed the presence of a novel domain (DDT) in bromodomain PHD finger transcription factors (BPTFs), chromatin remodeling factors of the BAZ-family and other putative nuclear proteins. This domain is characterized by a number of conserved aromatic and charged residues and is predicted to consist of three alpha helices. Recent studies indicate a likely DNA-binding function for the DDT domain.
197.
Post-translational GPI lipid anchor modification of proteins in kingdoms of life: analysis of protein sequence data from complete genomes.
2001 Jan; 14(1): 17-25. PubMed: 11287675.
Abstract + PDFTo investigate the occurrence of glycosylphosphatidylinositol (GPI) lipid anchor modification in various taxonomic ranges, potential substrate proteins have been searched for in completely sequenced genomes. We applied the big-pi predictor for the recognition of propeptide cleavage and anchor attachment sites with a new, generalized analytical form of the extreme-value distribution for evaluating false-positive prediction rates. (i) We find that GPI modification is present among lower and higher Eukaryota (approximately 0.5% of all proteins) but it seems absent in all eubacterial and three archaeobacterial species studied. Four other archaean genomes appear to encode such a fraction of substrate proteins (in the range of eukaryots) that they cannot be explained as false-positive predictions. This result supports the possible existence of GPI anchor modification in an archaean subgroup. (ii) The frequency of GPI-modified proteins on various chromosomes of a given eukaryotic species is different. (iii) Lists of potentially GPI-modified proteins in complete genomes with their predicted cleavage sites are available at http://mendel.imp.univie.ac.at/gpi/gpi_genomes.html. (iv) Orthologues of known transamidase subunits have been found only for EUKARYA: Inconsistencies in domain structure among homologues some of which may indicate sequencing errors are described. We present a refined model of the transamidase complex.
196.
Inversions and the dynamics of eukaryotic gene order.
2001 Jun; 17(6): 304-6. PubMed: 11377779.
Abstract + PDFComparisons of the gene order in closely related genomes reveal a major role for inversions in the genome shuffling process. In contrast to prokaryotes, where the inversions are predominantly large, half of the inversions between Saccharomyces cerevisiae and Candida albicans appear to be small, often encompassing only a single gene. Overall the genome rearrangement rate appears higher in eukaryotes than in prokaryotes, and the current genome data do not indicate that functional constraints on the co-expression of neighboring genes have a large role in conserving eukaryotic gene order. Nevertheless, qualitatively interesting examples of conservation of gene order in eukaryotes can be observed.
195.
The phylogenetic distribution of frataxin indicates a role in iron-sulfur cluster protein assembly.
2001 Oct 1; 10(21): 2463-8. PubMed: 11689493.
Abstract + PDFMuch has been learned about the cellular pathology of Friedreich's ataxia, a recessive neurodegenerative disease resulting from insufficient expression of the mitochondrial protein frataxin. However, the biochemical function of frataxin has remained obscure, hampering attempts at therapeutic intervention. To predict functional interactions of frataxin with other proteins we investigated whether its gene specifically co-occurs with any other genes in sequenced genomes. In 56 available genomes we identified two genes with identical phylogenetic distributions to the frataxin/cyaY gene: hscA and hscB/JAC1. These genes have not only emerged in the same evolutionary lineage as the frataxin gene, they have also been lost at least twice with it, and they have been horizontally transferred with it in the evolution of the mitochondria. The proteins encoded by hscA and hscB, the chaperone HSP66 and the co-chaperone HSP20, have been shown to be required for the synthesis of 2Fe-2S clusters on ferredoxin in proteobacteria. JAC1, an ortholog of hscB, and SSQ1, a paralog of hscA, have been shown to be required for iron-sulfur cluster assembly in mitochondria of Saccharomyces cerevisiae. Combining data on the co-occurrence of genes in genomes with experimental and predicted cellular localization data of their proteins supports the hypothesis that frataxin is directly involved in iron-sulfur cluster protein assembly. They indicate that frataxin is specifically involved in the same sub-process as HSP20/Jac1p.
194.
Quoderat demonstrandum? The mystery of experimental validation of apparently erroneous computational analyses of protein sequences.
Iyer LM, Aravind L, Bork P, Hofmann K, Mushegian AR, Zhulin IB, Koonin EV
2001; 2(12): RESEARCH0051. Epub 2001 Nov 13; PubMed: 11790254.
Abstract + PDFBACKGROUND: Computational predictions are critical for directing the experimental study of protein functions. Therefore it is paradoxical when an apparently erroneous computational prediction seems to be supported by experiment. RESULTS: We analyzed six cases where application of novel or conventional computational methods for protein sequence and structure analysis led to non-trivial predictions that were subsequently supported by direct experiments. We show that, on all six occasions, the original prediction was unjustified, and in at least three cases, an alternative, well-supported computational prediction, incompatible with the original one, could be derived. The most unusual cases involved the identification of an archaeal cysteinyl-tRNA synthetase, a dihydropteroate synthase and a thymidylate synthase, for which experimental verifications of apparently erroneous computational predictions were reported. Using sequence-profile analysis, multiple alignment and secondary-structure prediction, we have identified the unique archaeal 'cysteinyl-tRNA synthetase' as a homolog of extracellular polygalactosaminidases, and the 'dihydropteroate synthase' as a member of the beta-lactamase-like superfamily of metal-dependent hydrolases. CONCLUSIONS: In each of the analyzed cases, the original computational predictions could be refuted and, in some instances, alternative strongly supported predictions were obtained. The nature of the experimental evidence that appears to support these predictions remains an open question. Some of these experiments might signify discovery of extremely unusual forms of the respective enzymes, whereas the results of others could be due to artifacts.
193.
The Spir actin organizers are involved in vesicle transport processes.
Kerkhoff E, Simpson JC, Leberfinger CB, Otto IM, Doerks T, Bork P, Rapp UR, Raabe T, Pepperkok R
Abstract + PDFThe p150-Spir protein, which was discovered as a phosphorylation target of the Jun N-terminal kinase, is an essential regulator of the polarization of the Drosophila oocyte. Spir proteins are highly conserved between species and belong to the family of Wiskott-Aldrich homology region 2 (WH2) proteins involved in actin organization. The C-terminal region of Spir encodes a zinc finger structure highly homologous to FYVE motifs. A region with high homology between the Spir family proteins is located adjacent (N-terminal) to the modified FYVE domain and is designated as "Spir-box." The Spir-box has sequence similarity to a region of rabphilin-3A, which mediates interaction with the small GTPase Rab3A. Coexpression of p150-Spir and green fluorescent protein-tagged Rab GTPases in NIH 3T3 cells revealed that the Spir protein colocalized specifically with the Rab11 GTPase, which is localized at the trans-Golgi network (TGN), post-Golgi vesicles, and the recycling endosome. The distinct Spir localization pattern was dependent on the integrity of the modified FYVE finger motif and the Spir-box. Overexpression of a mouse Spir-1 dominant interfering mutant strongly inhibited the transport of the vesicular stomatitis virus G (VSV G) protein to the plasma membrane. The viral protein was arrested in membrane structures, largely colocalizing with the TGN marker TGN46. Our findings that the Spir actin organizer is targeted to intracellular membrane structures by its modified FYVE zinc finger and is involved in vesicle transport processes provide a novel link between actin organization and intracellular transport.
192.
Initial sequencing and analysis of the human genome.
Lander ES, Linton LM, Birren B, Nusbaum C, Zody MC, Baldwin J, Devon K, Dewar K, Doyle M, FitzHugh W, Funke R, Gage D, Harris K, Heaford A, Howland J, Kann L, Lehoczky J, Levine R, McEwan P, McKernan K, Meldrim J, Mesirov JP, Miranda C, Morris W, Naylor J, Raymond C, Rosetti M, Santos R, Sheridan A, Sougnez C, Stange-Thomann N, Stojanovic N, Subramanian A, Wyman D, Rogers J, Sulston J, Ainscough R, Beck S, Bentley D, Burton J, Clee C, Carter N, Coulson A, Deadman R, Deloukas P, Dunham A, Dunham I, Durbin R, French L, Grafham D, Gregory S, Hubbard T, Humphray S, Hunt A, Jones M, Lloyd C, McMurray A, Matthews L, Mercer S, Milne S, Mullikin JC, Mungall A, Plumb R, Ross M, Shownkeen R, Sims S, Waterston RH, Wilson RK, Hillier LW, McPherson JD, Marra MA, Mardis ER, Fulton LA, Chinwalla AT, Pepin KH, Gish WR, Chissoe SL, Wendl MC, Delehaunty KD, Miner TL, Delehaunty A, Kramer JB, Cook LL, Fulton RS, Johnson DL, Minx PJ, Clifton SW, Hawkins T, Branscomb E, Predki P, Richardson P, Wenning S, Slezak T, Doggett N, Cheng JF, Olsen A, Lucas S, Elkin C, Uberbacher E, Frazier M, Gibbs RA, Muzny DM, Scherer SE, Bouck JB, Sodergren EJ, Worley KC, Rives CM, Gorrell JH, Metzker ML, Naylor SL, Kucherlapati RS, Nelson DL, Weinstock GM, Sakaki Y, Fujiyama A, Hattori M, Yada T, Toyoda A, Itoh T, Kawagoe C, Watanabe H, Totoki Y, Taylor T, Weissenbach J, Heilig R, Saurin W, Artiguenave F, Brottier P, Bruls T, Pelletier E, Robert C, Wincker P, Smith DR, Doucette-Stamm L, Rubenfield M, Weinstock K, Lee HM, Dubois J, Rosenthal A, Platzer M, Nyakatura G, Taudien S, Rump A, Yang H, Yu J, Wang J, Huang G, Gu J, Hood L, Rowen L, Madan A, Qin S, Davis RW, Federspiel NA, Abola AP, Proctor MJ, Myers RM, Schmutz J, Dickson M, Grimwood J, Cox DR, Olson MV, Kaul R, Raymond C, Shimizu N, Kawasaki K, Minoshima S, Evans GA, Athanasiou M, Schultz R, Roe BA, Chen F, Pan H, Ramser J, Lehrach H, Reinhardt R, McCombie WR, de la Bastide M, Dedhia N, Blöcker H, Hornischer K, Nordsiek G, Agarwala R, Aravind L, Bailey JA, Bateman A, Batzoglou S, Birney E, Bork P, Brown DG, Burge CB, Cerutti L, Chen HC, Church D, Clamp M, Copley RR, Doerks T, Eddy SR, Eichler EE, Furey TS, Galagan J, Gilbert JG, Harmon C, Hayashizaki Y, Haussler D, Hermjakob H, Hokamp K, Jang W, Johnson LS, Jones TA, Kasif S, Kaspryzk A, Kennedy S, Kent WJ, Kitts P, Koonin EV, Korf I, Kulp D, Lancet D, Lowe TM, McLysaght A, Mikkelsen T, Moran JV, Mulder N, Pollara VJ, Ponting CP, Schuler G, Schultz J, Slater G, Smit AF, Stupka E, Szustakowski J, Thierry-Mieg D, Thierry-Mieg J, Wagner L, Wallis J, Wheeler R, Williams A, Wolf YI, Wolfe KH, Yang SP, Yeh RF, Collins F, Guyer MS, Peterson J, Felsenfeld A, Wetterstrand KA, Patrinos A, Morgan MJ, de Jong P, Catanese JJ, Osoegawa K, Shizuya H, Choi S, Chen YJ, Szustakowki J, International Human Genome Sequencing Consortium
Abstract + PDFThe human genome holds an extraordinary trove of information about human development, physiology, medicine and evolution. Here we report the results of an international collaboration to produce and make freely available a draft sequence of the human genome. We also present an initial analysis of the data, describing some of the insights that can be gleaned from the sequence.
191.
Evolution of tuf genes: ancient duplication, differential loss and gene conversion.
Lathe WC, Bork P
Abstract + PDFThe tuf gene of eubacteria, encoding the EF-tu elongation factor, was duplicated early in the evolution of the taxon. Phylogenetic and genomic location analysis of 20 complete eubacterial genomes suggests that this ancient duplication has been differentially lost and maintained in eubacteria.
190.
Frameshift peptide-derived T-cell epitopes: a source of novel tumor-specific antigens.
Linnebacher M, Gebert J, Rudy W, Woerner S, Yuan YP, Bork P, von Knebel Doeberitz M
2001 Jul 1; 93(1): 6-11. PubMed: 11391614.
Abstract + PDFMicrosatellite instability (MSI) caused by defective DNA mismatch repair (MMR) is a hallmark of hereditary nonpolyposis colorectal cancers (HNPCC) but also occurs in about 15% of sporadic tumors. If instability affects microsatellites in coding regions, translational frameshifts lead to truncated proteins often marked by unique frameshift peptide sequences at their C-terminus. Since MSI tumors show enhanced lymphocytic infiltration and our previous analysis identified numerous coding mono- and dinucleotide repeat-bearing candidate genes as targets of genetic instability, we examined the role of frameshift peptides in triggering cellular immune responses. Using peptide pulsed autologous CD40-activated B cells, we have generated cytotoxic T lymphocytes (CTL) that specifically recognize HLA-A2.1-restricted peptides derived from frameshift sequences. Among 16 frameshift peptides predicted from mutations in 8 different genes, 3 peptides conferred specific lysis of target cells exogenously loaded with cognate peptide. One peptide derived from a (-1) frameshift mutation in the TGFbetaIIR gene gave rise to a CTL bulk culture capable of lysing the MSI colorectal cancer cell line HCT116 carrying this frameshift mutation. Given the huge number of human coding microsatellites and assuming only a fraction being mutated and encoding immunologically relevant peptides in MSI tumors, frameshift protein sequences represent a novel subclass of tumor-specific antigens. It is tempting to speculate that a frameshift peptide-directed vaccination approach not only could offer new treatment modalities for existing MSI tumors but also might benefit asymptomatic at-risk individuals in HNPCC families by a prophylactic vaccination strategy.
189.
XplorMed: a tool for exploring MEDLINE abstracts.
2001 Sep; 26(9): 573-5. PubMed: 11551795.
Abstract + PDFThe most frequent access to the MEDLINE database of scientific abstracts is by keyword search. However, this is often not sufficient because although the user might find all the useful abstracts, these are buried in hundreds that are irrelevant. The exploratory tool XplorMed has been developed to analyse the result of any MEDLINE query. It suggests main groups of related topics and documents, sparing the user the need of reading all abstracts.
188.
Novel protein domains and repeats in Drosophila melanogaster: insights into structure, function, and evolution.
Ponting CP, Mott R, Bork P, Copley RR
2001 Dec; 11(12): 1996-2008. PubMed: 11731489.
Abstract + PDFSequence database searching methods such as BLAST, are invaluable for predicting molecular function on the basis of sequence similarities among single regions of proteins. Searches of whole databases however, are not optimized to detect multiple homologous regions within a single polypeptide. Here we have used the prospero algorithm to perform self-comparisons of all predicted Drosophila melanogaster gene products. Predicted repeats, and their homologs from all species, were analyzed further to detect hitherto unappreciated evolutionary relationships. Results included the identification of novel tandem repeats in the human X-linked retinitis pigmentosa type-2 gene product, repeated segments in cystinosin, associated with a defect in cystine transport, and 'nested' homologous domains in dysferlin, whose gene is mutated in limb girdle muscular dystrophy. Novel signaling domain families were found that may regulate the microtubule-based cytoskeleton and ubiquitin-mediated proteolysis, respectively. Two families of glycosyl hydrolases were shown to contain internal repetitions that hint at their evolution via a piecemeal, modular approach. In addition, three examples of fruit fly genes were detected with tandem exons that appear to have arisen via internal duplication. These findings demonstrate how completely sequenced genomes can be exploited to further understand the relationships between molecular structure, function, and evolution.
187.
Molecular characterization of a cDNA encoding functional human CLK4 kinase and localization to chromosome 5q35 [correction of 4q35].
Schultz J, Jones T, Bork P, Sheer D, Blencke S, Steyrer S, Wellbrock U, Bevec D, Ullrich A, Wallasch C
Abstract + PDFPhosphorylated serine- and arginine-rich (SR) proteins play an important role in the formation of spliceosomes, possibly controlling the regulation of alternative splicing. Enzymes that phosphorylate the SR proteins belong to the family of CDC2/CDC28-like kinases (CLK). Employing nucleotide sequence comparison of human expressed sequence tag sequences to the murine counterpart, we identified, cloned, and recombinantly expressed the human orthologue to the murine CLK4 cDNA. When fused to glutathione S-transferase, the catalytically active human CLK4 is able to autophosphorylate and to phosphorylate myelin basic protein, but not histone H2B as a substrate. Inspection of mRNA accumulation demonstrated gene expression in all human tissues, with the most prominent abundance in liver, kidney, brain, and heart. Using fluorescence in situ hybridization, the human CLK4 cDNA was localized to band q35 on chromosome 5 [corrected].
186.
Charting the proteomes of organisms with unsequenced genomes by MALDI-quadrupole time-of-flight mass spectrometry and BLAST homology searching.
Shevchenko A, Sunyaev SR, Loboda A, Shevchenko A, Bork P, Ens W, Standing KG
Abstract + PDFMALDI-quadrupole time-of-flight mass spectrometry was applied to identify proteins from organisms whose genomes are still unknown. The identification was carried out by successively searching a sequence database-first with a peptide mass fingerprint, then with a packet of noninterpreted MS/MS spectra, and finally with peptide sequences obtained by automated interpretation of the MS/MS spectra. A "MS BLAST" homology searching protocol was developed to overcome specific limitations imposed by mass spectrometric data, such as the limited accuracy of de novo sequence predictions. This approach was tested in a small-scale proteomic project involving the identification of 15 bands of gel-separated proteins from the methylotrophic yeast Pichia pastoris, whose genome has not yet been sequenced and which is only distantly related to other fungi.
185.
Integration of genome data and protein structures: prediction of protein folds, protein interactions and "molecular phenotypes" of single nucleotide polymorphisms.
2001 Feb; 11(1): 125-30. PubMed: 11179902.
Abstract + PDFWith the massive amount of sequence and structural data being produced, new avenues emerge for exploiting the information therein for applications in several fields. Fold distributions can be mapped onto entire genomes to learn about the nature of the protein universe and many of the interactions between proteins can now be predicted solely on the basis of the genomic context of their genes. Furthermore, by utilising the new incoming data on single nucleotide polymorphisms by mapping them onto three-dimensional structures of proteins, problems concerning population, medical and evolutionary genetics can be addressed.
184.
Prediction of deleterious human alleles.
2001 Mar 15; 10(6): 591-7. PubMed: 11230178.
Abstract + PDFSingle nucleotide polymorphisms (SNPs) constitute the bulk of human genetic variation, occurring with an average density of approximately 1/1000 nucleotides of a genotype. SNPs are either neutral allelic variants or are under selection of various strengths, and the impact of SNPs on fitness remains unknown. Identification of SNPs affecting human phenotype, especially leading to risks of complex disorders, is one of the key problems of medical genetics. SNPs in protein-coding regions that cause amino acid variants (non-synonymous cSNPs) are most likely to affect phenotypes. We have developed a straightforward and reliable method based on physical and comparative considerations that estimates the impact of an amino acid replacement on the three-dimensional structure and function of the protein. We estimate that approximately 20% of common human non-synonymous SNPs damage the protein. The average minor allele frequency of such SNPs in our data set was two times lower than that of benign non-synonymous SNPs. The average human genotype carries approximately 10(3) damaging non-synonymous SNPs that together cause a substantial reduction in fitness.
183.
Evolution of prokaryotic gene order: genome rearrangements in closely related species.
Suyama M, Bork P
2001 Jan; 17(1): 10-3. PubMed: 11163906.
Abstract + PDFConservation of gene order in prokaryotes has become important in predicting protein function because, over the evolutionary timescale, genomes are shuffled so that local gene-order conservation reflects the functional constraints within the protein. Here, we compare closely related genomes to identify the rate with which gene order is disrupted and to infer the genes involved in the genome rearrangement.
182.
Systematic identification of genes with coding microsatellites mutated in DNA mismatch repair-deficient cancer cells.
Woerner SM, Gebert J, Yuan YP, Sutter C, Ridder R, Bork P, von Knebel Doeberitz M
2001 Jul 1; 93(1): 12-9. PubMed: 11391615.
Abstract + PDFMicrosatellite instability (MSI) caused by deficient DNA mismatch-repair functions is a hallmark of cancers associated with the hereditary nonpolyposis colorectal cancer (HNPCC) syndrome but is also found in about 15% of all sporadic tumors. Most affected microsatellites reside in untranslated intergenic or intronic sequences. However, recently few genes with coding microsatellites were also shown to be mutational targets in MSI-positive cancers and might represent important mutation targets in their pathogenesis. The systematic identification of such genes and the analysis of their mutation frequency in MSI-positive cancers might thus reveal major clues to their functional role in MSI-associated carcinogenesis. We therefore initiated a systematic database search in 33,595 distinctly annotated human genes and identified 17,654 potentially coding mononucleotide repeats (cMNRs) and 2,028 coding dinucleotide repeats (cDNRs), which consist of n > or = 6 and n > or = 4 repeat units, respectively. Expression pattern and mutation frequency of 19 of these genes with the longest repeats were compared between DNA mismatch repair-deficient (MSI(+)) and proficient (MSS) cancer cells. Instability frequencies in these coding microsatellite genes ranged from 10% to 100% in MSI-H tumor cells, whereas MSS cancer cells did not show mutations. RT-PCR analysis further showed that most of the affected genes (10/15) were highly expressed in tumor cells. The approach outlined here identified a new set of genes frequently affected by mutations in MSI-positive tumor cells. It will lead to novel and highly specific diagnostic and therapeutic targets for microsatellite unstable cancers.
2000 32 publication(s).
181.
Automated extraction of information in molecular biology.
Andrade MA, Bork P
Abstract + PDFWe review data mining techniques in molecular biology, specifically those that extract information from the scientific literature itself. As more of the biological literature is published electronically, there is an opportunity, and even a need, to automatically summarize the literature in a customized way, for example by associating keywords to a topic. These keywords can be extracted from relevant publications. The process of keyword extraction can be automated and optimized to keep literature pointers automatically up-to-date or to filter relevant information from the literature. To illustrate these points, OMIM (Online Mendelian Inheritance in Man), a database of human inherited diseases, was linked to the literature and keywords were derived that covered distinct aspects such as genetic information on the one hand and disease-specific protein and phenotypic information on the other. They were used to extract information that is helpful for keeping entries about disease up-to-date.
180.
Homology-based method for identification of protein repeats using statistical significance estimates.
Andrade MA, Ponting CP, Gibson TJ, Bork P
2000 May 5; 298(3): 521-37. PubMed: 10772867.
Abstract + PDFShort protein repeats, frequently with a length between 20 and 40 residues, represent a significant fraction of known proteins. Many repeats appear to possess high amino acid substitution rates and thus recognition of repeat homologues is highly problematic. Even if the presence of a certain repeat family is known, the exact locations and the number of repetitive units often cannot be determined using current methods. We have devised an iterative algorithm based on optimal and sub-optimal score distributions from profile analysis that estimates the significance of all repeats that are detected in a single sequence. This procedure allows the identification of homologues at alignment scores lower than the highest optimal alignment score for non-homologous sequences. The method has been used to investigate the occurrence of eleven families of repeats in Saccharomyces cerevisiae, Caenorhabditis elegans and Homo sapiens accounting for 1055, 2205 and 2320 repeats, respectively. For these examples, the method is both more sensitive and more selective than conventional homology search procedures. The method allowed the detection in the SwissProt database of more than 2000 previously unrecognised repeats belonging to the 11 families. In addition, the method was used to merge several repeat families that previously were supposed to be distinct, indicating common phylogenetic origins for these families.
179.
Powers and pitfalls in sequence analysis: the 70% hurdle.
Bork P
2000 Apr; 10(4): 398-400. PubMed: 10779480.
PDF177.
Comparitve genome analysis: Exploiting the contect of genes to infer evolution and predict function
In: Comparitive Genomics pp.281-294. BID: 18.
ISBN: 0-7923-6583-6 Publisher: Kluwer Academic Publishers Printed in the Netherlands
Abstract + PDFDifferent gene context methods are reviewed and summarized and an example of implementing several of these strategies into a publicly accessible web server is given.
176.
EST comparison indicates 38% of human mRNAs contain possible alternative splice forms.
Brett D, Hanke J, Lehmann G, Haase S, Delbrück S, Krueger S, Reich J, Bork P
Abstract + PDFExpressed sequence tag (EST) databases represent a large volume of information on expressed genes including tissue type, expression profile and exon structure. In this study we create an extensive data set of human alternative splicing. We report the analysis of 7867 non-redundant mRNAs, 3011 of which contained alternative splice forms (38% of all mRNAs analysed). From a total of 12572 ESTs 4560 different possible alternative splice forms were detected. Interestingly, 70% of the alternative splice forms correspond to exon deletion events with only 30% exonic insertions. We experimentally verified 19 different splice forms from 16 genes in a total subset of 20 studied; all of the respective genes are of medical relevance.
175.
EST analysis online: WWW tools for detection of SNPs and alternative splice forms.
Brett D, Lehmann G, Hanke J, Gross S, Reich J, Bork P
2000 Sep; 16(9): 416-8. PubMed: 10973071.
PDF174.
HGBASE: a database of SNPs and other variations in and around human genes.
Brookes AJ, Lehväslaiho H, Siegfried M, Boehm JG, Yuan YP, Sarkar CM, Bork P, Ortigao F
2000 Jan 1; 28(1): 356-60. PubMed: 10592273.
Abstract + PDFHuman genome polymorphism is expected to play a key role in defining the etiologic basis of phenotypic differences between individuals in aspects such as drug responses and common disease predisposition. Relevant functional DNA changes will probably be located in or near to transcribed sequences, and include many single nucleotide polymorphisms. To aid the future analysis of such genome variation, HGBASE (Human Genic Bi-Allelic SEquences) was constructed as a means to gather human gene-linked polymorphisms from all possible public sources, and show these as a non-redundant set of records in a standardized and user-friendly database endowed with text and sequence based search facilities. After 1 year of presence on the WWW, the HGBASE project has compiled data for over 22 000 records, and this number continues to triple every 6-12 months with data harvested or submitted from all major public genome databases and published literature from the previous decade. Extensive annotation enhancement, internal consistency checking and manual review of every record is undertaken to address potential errors and deficiencies sometimes present in the original source data. The fully polished and comprehensive database is made freely available to all at http://hgbase.cgr.ki.se
173.
Homology among (betaalpha)(8) barrels: implications for the evolution of metabolic pathways.
Copley RR, Bork P
2000 Nov 3; 303(4): 627-41. PubMed: 11054297.
Abstract + PDFWe provide statistically reliable sequence evidence indicating that at least 12 of 23 SCOP (betaalpha)(8) (TIM) barrel superfamilies share a common origin. This includes all but one of the known and predicted TIM barrels found in central metabolism. The statistical evidence is complemented by an examination of the details of protein structure, with certain structural locations favouring catalytic residues even though the nature of their molecular function may change. The combined analysis of sequence, structure and function also enables us to propose a phylogeny of TIM barrels. Based on these data, we are able to examine differing theories of pathway and enzyme evolution, by mapping known TIM barrel folds to the pathways of central metabolism. The results favour widespread recruitment of enzymes between pathways, rather than a "backwards evolution" model, and support the idea that modern proteins may have arisen from common ancestors that bound key metabolites.
172.
Re-annotating the Mycoplasma pneumoniae genome sequence: adding value, function and reading frames.
Dandekar T, Huynen MA, Regula JT, Ueberle B, Zimmermann CU, Andrade MA, Doerks T, Sánchez-Pulido L, Snel B, Suyama M, Yuan YP, Herrmann R, Bork P
2000 Sep 1; 28(17): 3278-88. PubMed: 10954595.
Abstract + PDFFour years after the original sequence submission, we have re-annotated the genome of Mycoplasma pneumoniae to incorporate novel data. The total number of ORFss has been increased from 677 to 688 (10 new proteins were predicted in intergenic regions, two further were newly identified by mass spectrometry and one protein ORF was dismissed) and the number of RNAs from 39 to 42 genes. For 19 of the now 35 tRNAs and for six other functional RNAs the exact genome positions were re-annotated and two new tRNA(Leu) and a small 200 nt RNA were identified. Sixteen protein reading frames were extended and eight shortened. For each ORF a consistent annotation vocabulary has been introduced. Annotation reasoning, annotation categories and comparisons to other published data on M.pneumoniae functional assignments are given. Experimental evidence includes 2-dimensional gel electrophoresis in combination with mass spectrometry as well as gene expression data from this study. Compared to the original annotation, we increased the number of proteins with predicted functional features from 349 to 458. The increase includes 36 new predictions and 73 protein assignments confirmed by the published literature. Furthermore, there are 23 reductions and 30 additions with respect to the previous annotation. mRNA expression data support transcription of 184 of the functionally unassigned reading frames.
171.
Anopheles gambiae pilot gene discovery project: identification of mosquito innate immunity genes from expressed sequence tags generated from immune-competent cell lines.
Dimopoulos G, Casavant TL, Chang S, Scheetz T, Roberts C, Donohue M, Schultz J, Benes V, Bork P, Ansorge W, Soares MB, Kafatos FC
2000 Jun 6; 97(12): 6619-24. PubMed: 10841561.
Abstract + PDFTogether with AIDS and tuberculosis, malaria is at the top of the list of devastating infectious diseases. However, molecular genetic studies of its major vector, Anopheles gambiae, are still quite limited. We have conducted a pilot gene discovery project to accelerate progress in the molecular analysis of vector biology, with emphasis on the mosquito's antimalarial immune defense. A total of 5,925 expressed sequence tags were determined from normalized cDNA libraries derived from immune-responsive hemocyte-like cell lines. The 3,242 expressed sequence tag-containing cDNA clones were grouped into 2,380 clone clusters, potentially representing unique genes. Of these, 1,118 showed similarities to known genes from other organisms, but only 27 were identical to previously known mosquito genes. We identified 38 candidate genes, based on sequence similarity, that may be implicated in immune reactions including antimalarial defense; 19 of these were shown experimentally to be inducible by bacterial challenge, lending support to their proposed involvement in mosquito immunity.
170.
L27, a novel heterodimerization domain in receptor targeting proteins Lin-2 and Lin-7.
Doerks T, Bork P, Kamberov E, Makarova O, Muecke S, Margolis B
2000 Jul; 25(7): 317-8. PubMed: 10871881.
PDF169.
GRAM, a novel domain in glucosyltransferases, myotubularins and other putative membrane-associated proteins.
Doerks T, Strauss M, Brendel M, Bork P
2000 Oct; 25(10): 483-5. PubMed: 11050430.
PDF168.
Automated annotation of GPI anchor sites: case study C. elegans.
2000 Jul; 25(7): 340-1. PubMed: 10871885.
PDF167.
Functional genomic analysis of cell division in C. elegans using RNAi of genes on chromosome III.
Gönczy P, Echeverri C, Oegema K, Coulson A, Jones SJ, Copley RR, Duperon J, Oegema J, Brehm M, Cassin E, Hannak E, Kirkham M, Pichler S, Flohrs K, Goessen A, Leidel S, Alleaume AM, Martin C, Ozlü N, Bork P, Hyman AA
Abstract + PDFGenome sequencing projects generate a wealth of information; however, the ultimate goal of such projects is to accelerate the identification of the biological function of genes. This creates a need for comprehensive studies to fill the gap between sequence and function. Here we report the results of a functional genomic screen to identify genes required for cell division in Caenorhabditis elegans. We inhibited the expression of approximately 96% of the approximately 2,300 predicted open reading frames on chromosome III using RNA-mediated interference (RNAi). By using an in vivo time-lapse differential interference contrast microscopy assay, we identified 133 genes (approximately 6%) necessary for distinct cellular processes in early embryos. Our results indicate that these genes represent most of the genes on chromosome III that are required for proper cell division in C. elegans embryos. The complete data set, including sample time-lapse recordings, has been deposited in an open access database. We found that approximately 47% of the genes associated with a differential interference contrast phenotype have clear orthologues in other eukaryotes, indicating that this screen provides putative gene functions for other species as well.
166.
TAP (NXF1) belongs to a multigene family of putative RNA export factors with a conserved modular architecture.
Herold A, Suyama M, Rodrigues JP, Braun IC, Kutay U, Carmo-Fonseca M, Bork P, Izaurralde E
2000 Dec; 20(23): 8996-9008. PubMed: 11073998.
Abstract + PDFVertebrate TAP (also called NXF1) and its yeast orthologue, Mex67p, have been implicated in the export of mRNAs from the nucleus. The TAP protein includes a noncanonical RNP-type RNA binding domain, four leucine-rich repeats, an NTF2-like domain that allows heterodimerization with p15 (also called NXT1), and a ubiquitin-associated domain that mediates the interaction with nucleoporins. Here we show that TAP belongs to an evolutionarily conserved family of proteins that has more than one member in higher eukaryotes. Not only the overall domain organization but also residues important for p15 and nucleoporin interaction are conserved in most family members. We characterize two of four human TAP homologues and show that one of them, NXF2, binds RNA, localizes to the nuclear envelope, and exhibits RNA export activity. NXF3, which does not bind RNA or localize to the nuclear rim, has no RNA export activity. Database searches revealed that although only one p15 (nxt) gene is present in the Drosophila melanogaster and Caenorhabditis elegans genomes, there is at least one additional p15 homologue (p15-2 [also called NXT2]) encoded by the human genome. Both human p15 homologues bind TAP, NXF2, and NXF3. Together, our results indicate that the TAP-p15 mRNA export pathway has diversified in higher eukaryotes compared to yeast, perhaps reflecting a greater substrate complexity.
165.
Predicting protein function by genomic context: quantitative evaluation and qualitative inferences.
2000 Aug; 10(8): 1204-10. PubMed: 10958638.
Abstract + PDFVarious new methods have been proposed to predict functional interactions between proteins based on the genomic context of their genes. The types of genomic context that they use are Type I: the fusion of genes; Type II: the conservation of gene-order or co-occurrence of genes in potential operons; and Type III: the co-occurrence of genes across genomes (phylogenetic profiles). Here we compare these types for their coverage, their correlations with various types of functional interaction, and their overlap with homology-based function assignment. We apply the methods to Mycoplasma genitalium, the standard benchmarking genome in computational and experimental genomics. Quantitatively, conservation of gene order is the technique with the highest coverage, applying to 37% of the genes. By combining gene order conservation with gene fusion (6%), the co-occurrence of genes in operons in absence of gene order conservation (8%), and the co-occurrence of genes across genomes (11%), significant context information can be obtained for 50% of the genes (the categories overlap). Qualitatively, we observe that the functional interactions between genes are stronger as the requirements for physical neighborhood on the genome are more stringent, while the fraction of potential false positives decreases. Moreover, only in cases in which gene order is conserved in a substantial fraction of the genomes, in this case six out of twenty-five, does a single type of functional interaction (physical interaction) clearly dominate (>80%). In other cases, complementary function information from homology searches, which is available for most of the genes with significant genomic context, is essential to predict the type of interaction. Using a combination of genomic context and homology searches, new functional features can be predicted for 10% of M. genitalium genes.
164.
Exploitation of gene context.
2000 Jun; 10(3): 366-70. PubMed: 10851194.
Abstract + PDFRecently, a number of techniques have been proposed that use completely sequenced genomes for the function prediction of individual proteins encoded therein. They use the fusion of genes, their conserved location in operons or merely their co-occurrence in genomes to predict the existence of functional interactions between the proteins they encode. This type of information complements functional features that are predicted by classical homology-based search techniques.
163.
Discovery, scoring and utilization of human single nucleotide polymorphisms: a multidisciplinary problem.
Isaksson A, Landegren U, Syvänen AC, Bork P, Stein C, Ortigao F, Brookes AJ
2000 Feb; 8(2): 154-6. PubMed: 10757651.
Abstract + PDFThere are great hopes that the most common form of human genetic variation, single nucleotide polymorphisms (SNPs), can be used to improve radically biological understanding and to advance medicine. However, considerable controversy exists over just how SNPs can be applied to gain these insights. The second international SNP meeting, held at Schloss Hohenkammer, Munich, Germany, brought together leading international scientists from academia and industry to look at these issues from a multidisciplinary perspective. Topics that were covered spanned SNP discovery, scoring technologies, population genetics, disease studies, commercial dimensions, pharmacogenomics, bioinformatics, and legal considerations. SNP discovery is picking up speed; The SNP Consortium (TSC) is set to produce 300,000 publicly available SNPs within 2 years. Improved technologies for scoring SNPs are reducing hands-on time and cost, although truly high-throughput methods are still lacking for genome-wide population-based studies. Large numbers of SNPs have already been analysed in diverse populations. The results emphasise the importance of considering population history when using SNPs to search for genetic risk factors. Opinions on the feasibility of extensive SNP-based analysis of complex disease vary. However, combining expertise from several fields will be key to achieving optimal utilization of SNPs.
162.
Gene context conservation of a higher order than operons.
2000 Oct; 25(10): 474-9. PubMed: 11050428.
Abstract + PDFOperons, co-transcribed and co-regulated contiguous sets of genes, are poorly conserved over short periods of evolutionary time. The gene order, gene content and regulatory mechanisms of operons can be very different, even in closely related species. Here, we present several lines of evidence which suggest that, although an operon and its individual genes and regulatory structures are rearranged when comparing the genomes of different species, this rearrangement is a conservative process. Genomic rearrangements invariably maintain individual genes in very specific functional and regulatory contexts. We call this conserved context an uber-operon.
161.
The p150-Spir protein provides a link between c-Jun N-terminal kinase function and actin reorganization.
Otto IM, Raabe T, Rennefahrt UE, Bork P, Rapp UR, Kerkhoff E
Abstract + PDFThe Jun N-terminal kinase (JNK) is a downstream effector of Rac and Cdc42 GTPases involved in actin reorganization [1-3]. A role of the Drosophila JNK homologue, Basket (DJNK/Bsk), in the regulation of cell shape changes and actin reorganization arises from its function in the process of dorsal closure [4-6]. One potential mechanism for induction of cytoskeletal changes by JNK is via transcriptional activation of the decapentaplegic gene (dpp, a member of the TGFbeta superfamily) [6]. A direct link between JNK signalling and actin organization has not yet been found, however. We have identified a novel DJNK-interacting protein, p150-Spir, that belongs to the Wiscott-Aldrich syndrome protein (WASP) homology domain 2 (WH2) family of proteins involved in actin reorganization [7] [8]. It is a multidomain protein with a cluster of four WH2 domains, a modified FYVE zinc-finger motif [9], and a DEJL motif, a docking site for JNK [10], at its carboxy-terminal end. In mouse fibroblasts, p150-Spir colocalized with F-actin and its overexpression induced clustering of filamentous actin around the nucleus. When coexpressed with p150-Spir in NIH 3T3 cells, JNK translocated to and colocalizes with p150-Spir at discrete spots around the nucleus. Carboxy-terminal sequences of p150-Spir were phosphorylated by JNK both in vitro and in vivo. We conclude that p150-Spir is a downstream target of JNK function and provides a direct link between JNK and actin organization.
159.
SMART: a web-based tool for the study of genetically mobile domains.
2000 Jan 1; 28(1): 231-4. PubMed: 10592234.
Abstract + PDFSMART (a Simple Modular Architecture Research Tool) allows the identification and annotation of genetically mobile domains and the analysis of domain architectures (http://SMART.embl-heidelberg.de ). More than 400 domain families found in signalling, extra-cellular and chromatin-associated proteins are detectable. These domains are extensively annotated with respect to phyletic distributions, functional class, tertiary structures and functionally important residues. Each domain found in a non-redundant protein database as well as search parameters and taxonomic information are stored in a relational database system. User interfaces to this database allow searches for proteins containing specific combinations of domains in defined taxa.
158.
More than 1,000 putative new human signalling proteins revealed by EST data mining.
Abstract + PDFCloning procedures aided by homology searches of EST databases have accelerated the pace of discovery of new genes, but EST database searching remains an involved and onerous task. More than 1.6 million human EST sequences have been deposited in public databases, making it difficult to identify ESTs that represent new genes. Compounding the problems of scale are difficulties in detection associated with a high sequencing error rate and low sequence similarity between distant homologues. We have developed a new method, coupling BLAST-based searches with a domain identification protocol, that filters candidate homologues. Application of this method in a large-scale analysis of 100 signalling domain families has led to the identification of ESTs representing more than 1,000 novel human signalling genes. The 4,206 publicly available ESTs representing these genes are a valuable resource for rapid cloning of novel human signalling proteins. For example, we were able to identify ESTs of at least 106 new small GTPases, of which 6 are likely to belong to new subfamilies. In some cases, further analyses of genomic DNA led to the discovery of previously unidentified full-length protein sequences. This is exemplified by the in silico cloning (prediction of a gene product sequence using only genomic and EST sequence data) of a new type of GTPase with two catalytic domains.
156.
STRING: a web-server to retrieve and display the repeatedly occurring neighbourhood of a gene.
2000 Sep 15; 28(18): 3442-4. PubMed: 10982861.
Abstract + PDFThe repeated occurrence of genes in each other's neighbourhood on genomes has been shown to indicate a functional association between the proteins they encode. Here we introduce STRING (search tool for recurring instances of neighbouring genes), a tool to retrieve and display the genes a query gene repeatedly occurs with in clusters on the genome. The tool performs iterative searches and visualises the results in their genomic context. By finding the genomically associated genes for a query, it delineates a set of potentially functionally associated genes. The usefulness of STRING is illustrated with an example that suggests a functional context for an RNA methylase with unknown specificity.
155.
REF, an evolutionary conserved family of hnRNP-like proteins, interacts with TAP/Mex67p and participates in mRNA nuclear export.
Stutz F, Bachi A, Doerks T, Braun IC, Séraphin B, Wilm M, Bork P, Izaurralde E
Abstract + PDFVertebrate TAP and its yeast ortholog Mex67p are involved in the export of messenger RNAs from the nucleus. TAP has also been implicated in the export of simian type D viral RNAs bearing the constitutive transport element (CTE). Although TAP directly interacts with CTE-bearing RNAs, the mode of interaction of TAP/Mex67p with cellular mRNAs is different from that with the CTE RNA and is likely to be mediated by protein-protein interactions. Here we show that Mex67p directly interacts with Yra1p, an essential yeast hnRNP-like protein. This interaction is evolutionarily conserved as Yra1p also interacts with TAP. Conditional expression in yeast cells implicates Yra1 p in the export of cellular mRNAs. Database searches revealed that Yra1p belongs to an evolutionarily conserved family of hnRNP-like proteins having more than one member in Mus musculus, Xenopus laevis, Caenorhabditis elegans, and Schizosaccharomyces pombe and at least one member in several species including plants. The murine members of the family directly interact with TAP. Because members of this protein family are characterized by the presence of one RNP-motif RNA-binding domain and exhibit RNA-binding activity, we called these proteins REF-bps for RNA and export factor binding proteins. Thus, Yra1p and members of the REF family of hnRNP-like proteins may facilitate the interaction of TAP/Mex67p with cellular mRNAs.
154.
Individual variation in protein-coding sequences of human genome.
2000; 54: 409-37. PubMed: 10829234.
PDF153.
SNP frequencies in human genes an excess of rare alleles and differing modes of selection.
2000 Aug; 16(8): 335-7. PubMed: 10904261.
PDF152.
Towards a structural basis of human non-synonymous single nucleotide polymorphisms.
2000 May; 16(5): 198-200. PubMed: 10782110.
PDF151.
Prediction of structural domains of TAP reveals details of its interaction with p15 and nucleoporins.
Abstract + PDFVertebrate TAP is a nuclear mRNA export factor homologous to yeast Mex67p. The middle domain of TAP binds directly to p15, a protein related to the nuclear transport factor 2 (NTF2), whereas its C-terminal domain interacts with various nucleoporins, the components of the nuclear pore complex (NPC). Here, we report that the middle domain of TAP is also similar to NTF2, as well as to regions in Ras-GAP SH3 domain binding protein (G3BP) and some plant protein kinases. Based on the known three-dimensional structure of NTF2 homodimer, a heterodimerization model of TAP and p15 could be inferred. This model was confirmed by site-directed mutagenesis of residues located at the dimer interface. Furthermore, the C-terminus of TAP was found to contain a ubiquitin-associated (UBA) domain. By site-directed mutagenesis we show that a conserved loop in this domain plays an essential role in mediating TAP-nucleoporin interaction.
150.
NAIL-Network Analysis Interface for Linking HMMER results.
2000 Jul; 16(7): 656-7. PubMed: 11038338.
Abstract + PDFSUMMARY: Network Analysis Interface for Linking HMMER results (NAIL) is a web-based tool for the analysis of results from a HMMER protein database-search. NAIL facilitates the selection of protein hits and the creation of an alignment, which can be used for a new sequence similarity search.
1999 27 publication(s).
149.
Applying logic programming to derive novel functional information of genomes.
Bansal A, Bork P
In: lecture notes in computer sciences: Practical aspects of declarative languages. (Gupta, G.)1551 pp.275-289. BID: 7.
Publisher: Springer, New York
148.
A lipid-binding domain in Wnt: a case of mistaken identity?
Barnes MR, Russell RB, Copley RR, Ponting CP, Bork P, Cumberledge S, Reichsman F, Moore HM
PDF146.
Genome Comparsions to Monitor Molecular Evolution.
In: Microbial Evolution and Infection. (Goebel, U.B., Ruf, B.R.) pp.80-92. BID: 8.
Publisher: Einhorn-Presse Verlag Reinbek
145.
Domains in plexins: links to integrins and transcription factors.
1999 Jul; 24(7): 261-3. PubMed: 10390613.
PDF144.
A point of entry into genomics. (book review).
Bork P, Huynen MA
1999 Nov 1; 23(3): 273. PID: 300.
PDF143.
Phospholipases A2 and Wnts are unlikely to share a common ancestor.
Copley RR, Ponting CP, Bork P
PDF142.
Protein families in multicellular organisms.
1999 Jun; 9(3): 408-15. PubMed: 10361098.
Abstract + PDFThe complete sequence of the nematode worm Caenorhabditis elegans contains the genetic machinery that is required to undertake the core biological processes of single cells. However, the genome also encodes proteins that are associated with multicellularity, as well as others that are lineage-specific expansions of phylogenetically widespread families and yet more that are absent in non-nematodes. Ongoing analysis is beginning to illuminate the similarities and differences among human proteins and proteins that are encoded by the genomes of the multicellular worm and the unicellular yeast, and will be essential in determining the reliability of transferring experimental data among phylogenetically distant species.
141.
Pathway alignment: application to the comparative analysis of glycolytic enzymes.
Abstract + PDFComparative analysis of metabolic pathways in different genomes yields important information on their evolution, on pharmacological targets and on biotechnological applications. In this study on glycolysis, three alternative ways of comparing biochemical pathways are combined: (1) analysis and comparison of biochemical data, (2) pathway analysis based on the concept of elementary modes, and (3) a comparative genome analysis of 17 completely sequenced genomes. The analysis reveals a surprising plasticity of the glycolytic pathway. Isoenzymes in different species are identified and compared; deviations from the textbook standard are detailed. Several potential pharmacological targets and by-passes (such as the Entner-Doudoroff pathway) to glycolysis are examined and compared in the different species. Archaean, bacterial and parasite specific adaptations are identified and described.
140.
Prediction of potential GPI-modification sites in proprotein sequences.
1999 Sep 24; 292(3): 741-58. PubMed: 10497036.
Abstract + PDFGlycosylphosphatidylinositol (GPI) lipid anchoring is a common posttranslational modification known mainly from extracellular eukaryotic proteins. Attachment of the GPI moiety to the carboxyl terminus (omega-site) of the polypeptide follows after proteolytic cleavage of a C-terminal propeptide. For the first time, a new prediction technique locating potential GPI-modification sites in precursor sequences has been applied for large-scale protein sequence database searches. The composite prediction function (with separate parametrisation for metazoan and protozoan proteins) consists of terms evaluating both amino acid type preferences at sequence positions near a supposed omega-site as well as the concordance with general physical properties encoded in multi-residue correlation within the motif sequence. The latter terms are especially successful in rejecting non-appropriate sequences from consideration. The algorithm has been validated with a self-consistency and two jack-knife tests for the learning set of fully annotated sequences from the SWISS-PROT database as well as with a newly created database "big-Pi" (more than 300 GPI-motif mutations extracted from original literature sources). The accuracy of predicting the effect of mutations in the GPI sequence motif was above 83 %. Lists of potential precursor proteins which are non-annotated in SWISS-PROT and SPTrEMBL are presented on the WWW-page http://www.embl-heidelberg.de/beisenha/gpi/gpi_p rediction. html The algorithm has been implemented in the prototype software "big-Pi predictor" which may find application as a genome annotation and target selection tool.
139.
Evaluation of human-readable annotation in biomolecular sequence databases with biological rule libraries.
Eisenhaber F, Bork P
1999 Jul-Aug; 15(7-8): 528-35. PubMed: 10487860.
Abstract + PDFMOTIVATION: Computer-based selection of entries from sequence databases with respect to a related functional description, e.g. with respect to a common cellular localization or contributing to the same phenotypic function, is a difficult task. Automatic semantic analysis of annotations is not only hampered by incomplete functional assignments. A major problem is that annotations are written in a rich, non-formalized language and are meant for reading by a human expert. This person can extract from the text considerably more information than is immediately apparent due to his extended biological background knowledge and logical reasoning. APPROACH: A technique of automated annotation evaluation based on a combination of lexical analysis and the usage of biological rule libraries has been developed. The proposed algorithm generates new functional descriptors from the annotation of a given entry using the semantic units of the annotation as prepositions for implications executed in accordance with the rule library. RESULTS: The prototype of a software system, the Meta_A(nnotator) program, is described and the results of its application to sequence attribute assignment and sequence selection problems, such as cellular localization and sequence domain annotation of SWISS-PROT entries, are presented. The current software version assigns useful subcellular localization qualifiers to approximately 88% of all SWISS-PROT entries. As shown by demonstrative examples, the combination of sequence and annotation analysis is a powerful approach for the detection of mutual annotation/sequence inconsistencies. AVAILABILITY: Results for the cellular localization assignment can be viewed at the URL http://www.bork. embl-heidelberg.de/CELL_LOC/CELL_LOC.html.
138.
Aligning sequences
Gibson TJ, Bork P
In: Encyclopedia of Molecular Biology (Ed. Thomas E. Creighton) pp.2320-2324. BID: 9.
ISBN: 0-471-15302-8 Publisher: John Wiley & Sons, Inc. A Wiley-Interscience Publication
Abstract + PDFsequence analysis: aligning protein or nucleotide sequences
137.
Alternative splicing of human genes: more the rule than the exception?
Hanke J, Brett D, Zastrow I, Aydin A, Delbrück S, Lehmann G, Luft F, Reich J, Bork P
1999 Oct; 15(10): 389-90. PubMed: 10498933.
PDF136.
Associative database of protein sequences.
Hanke J, Lehmann G, Bork P, Reich JG
1999 Sep; 15(9): 741-8. PubMed: 10498774.
Abstract + PDFMOTIVATION: We present a new concept that combines data storage and data analysis in genome research, based on an associative network memory. As an illustration, 115 000 conserved regions from over 73 000 published sequences (i.e. from the entire annotated part of the SWISSPROT sequence database) were identified and clustered by a self-organizing network. Similarity and kinship, as well as degree of distance between the conserved protein segments, are visualized as neighborhood relationship on a two-dimensional topographical map. RESULTS: Such a display overcomes the restrictions of linear list processing and allows local and global sequence relationships to be studied visually. Families are memorized as prototype vectors of conserved regions. On a massive parallel machine, clustering and updating of the database take only a few seconds; a rapid analysis of incoming data such as protein sequences or ESTs is carried out on present-day workstations. AVAILABILITY: Access to the database is available at http://www.bioinf.mdc-berlin.de/unter2.html++ + CONTACT: (hanke,lehmann,reich)@mdc-berlin.de; bork@embl-heidelberg.de
135.
Variation and evolution of the citric-acid cycle: a genomic perspective.
1999 Jul; 7(7): 281-91. PubMed: 10390638.
Abstract + PDFThe presence of genes encoding enzymes involved in the citric-acid cycle has been studied in 19 completely sequenced genomes. In the majority of species, the cycle appears to be incomplete or absent. Several distinct, incomplete cycles reflect adaptations to different environments. Their distribution over the phylogenetic tree hints at precursors in the evolution of the citric-acid cycle.
134.
Lateral Gene Transfer, Genome Surveys and the Phylogeny of Prokaryotes.
1999 Nov 19; 286(5444): 1443. PID: 293.
Abstract + PDFDoolittle argued that to construct phylogenies, an organism should be regarded as either less or more than the sum of its genes (1). The argument is based on the observation that gene phylogenies are rarely consistent with one another because, among others, of lateral gene transfer (LGT). Creating phylogenies from sequence data in which an organism is described exactly as the sum of its genes is not, however, the only approach (2). Rather than creating phylogenies based on sequence identity for separate genes, this alternative creates a distance-based phylogeny at the genome level by comparing the fraction of genes shared between genomes (2). The resulting phylogeny (Fig. 1) of completely sequenced genomes (for an overview, see http://www.tigr.org/tdb/tdb.html) is remarkably similar to the phylogenies that are based on 16S ribosomal RNA (3). Not only is the trichotomy between Eukarya, Bacteria, and Archaea present, but within each of these taxa the clusters generally recognized as being monophyletic and for which multiple genomes are available, all have high bootstrap values (the Proteobacteria and their branching order, the Spirochaetales, the low (G+C) Gram-positive bacteria, and the Euryarchaeota). This method does not resolve the major branchings of the Bacteria, but neither do the phylogenies based on sequences that do not show LGT resolve this part of Bacterial phylogeny with a high degree of confidence.
133.
The three-dimensional structure of the HRDC domain and implications for the Werner and Bloom syndrome proteins.
Liu Z, Macias MJ, Bottomley MJ, Stier G, Linge JP, Nilges M, Bork P, Sattler M
Abstract + PDFBACKGROUND: The HRDC (helicase and RNaseD C-terminal) domain is found at the C terminus of many RecQ helicases, including the human Werner and Bloom syndrome proteins. RecQ helicases have been shown to unwind DNA in an ATP-dependent manner. However, the specific functional roles of these proteins in DNA recombination and replication are not known. An HRDC domain exists in both of the human RecQ homologues that are implicated in human disease and may have an important role in their function. RESULTS: We have determined the three-dimensional structure of the HRDC domain in the Saccharomyces cerevisiae RecQ helicase Sgs1p by nuclear magnetic resonance (NMR) spectroscopy. The structure resembles auxiliary domains in bacterial DNA helicases and other proteins that interact with nucleic acids. We show that a positively charged region on the surface of the Sgs1p HRDC domain can interact with DNA. Structural similarities to bacterial DNA helicases suggest that the HRDC domain functions as an auxiliary domain in RecQ helicases. Homology models of the Werner and Bloom HRDC domains show different surface properties when compared with Sgs1p. CONCLUSIONS: The HRDC domain represents a structural scaffold that resembles auxiliary domains in proteins that are involved in nucleic acid metabolism. In Sgs1p, the HRDC domain could modulate the helicase function via auxiliary contacts to DNA. However, in the Werner and Bloom syndrome helicases the HRDC domain may have a role in their functional differences by mediating diverse molecular interactions.
132.
A novel transactivation domain in parkin.
Morett E, Bork P
1999 Jun; 24(6): 229-31. PubMed: 10366851.
PDF131.
Domain organization of Mac-2 binding protein and its oligomerization to linear and ring-like structures.
Müller SA, Sasaki T, Bork P, Wolpensinger B, Schulthess T, Timpl R, Engel A, Engel J
1999 Aug 27; 291(4): 801-13. PubMed: 10452890.
Abstract + PDFThe multidomain Mac-2 binding protein (M2BP) is present in serum and in the extracellular matrix in the form of linear and ring-shaped oligomers, which interact with galectin-3, fibronectin, collagens, integrins and other large glycoproteins. Domain 1 of M2BP (M2BP-1) shows homology with the cysteine-rich SRCR domain of scavanger receptor. Domains 2 and 3 are related to the dimerization domains BTB/POZ and IVR of the Drosophila kelch protein. Recombinant M2BP, its N-terminal domain M2BP-1 and a fragment consisting of putative domains 2, 3 and 4 (M2BP-2,3,4) were investigated by scanning transmission electron microscopy, transmission electron microscopy, analytical ultracentrifugation and binding assays. The ring oligomers formed by the intact protein are comprised of approximately 14 nm long segments composed of two 92 kDa M2BP monomers. Although the rings vary in size, decamers predominate. The various linear oligomers also observed are probably ring precursors, dimers predominate. M2BP-1 exhibits a native fold, does not oligomerize and is inactive in cell attachment. M2BP-2,3,4 aggregates to heterogeneous, protein filled ring-like structures as shown by metal shadowed preparations. These aggregates retain the cell-adhesive potential indicating native folding. It is hypothesized that the rings provide an interaction pattern for multivalent interactions of M2BP with target molecules or complexes of ligands.
130.
The mahogany protein is a receptor involved in suppression of obesity.
Nagle DL, McGrail SH, Vitale J, Woolf EA, Dussault BJ, DiRocco L, Holmgren L, Montagno J, Bork P, Huszar D, Fairchild-Huntress V, Ge P, Keilty J, Ebeling C, Baldini L, Gilchrist J, Burn P, Carlson GA, Moore KJ
Abstract + PDFGenetic studies have shown that mutations within the mahogany locus suppress the pleiotropic phenotypes, including obesity, of the agouti-lethal-yellow mutant. Here we identify the mahogany gene and its product; this study, to our knowledge, represents the first positional cloning of a suppressor gene in the mouse. Expression of the mahogany gene is broad; however, in situ hybridization analysis emphasizes the importance of its expression in the ventromedial hypothalamic nucleus, a region that is intimately involved in the regulation of body weight and feeding. We present new genetic studies that indicate that the mahogany locus does not suppress the obese phenotype of the melanocortin-4-receptor null allele or those of the monogenic obese models (Lep(db), tub and Cpe(fat)). However, mahogany can suppress diet-induced obesity, the mechanism of which is likely to have implications for therapeutic intervention in common human obesity. The amino-acid sequence of the mahogany protein suggests that it is a large, single-transmembrane-domain receptor-like molecule, with a short cytoplasmic tail containing a site that is conserved between Caenorhabditis elegans and mammals. We propose two potential, alternative modes of action for mahogany: one draws parallels with the mechanism of action of low-affinity proteoglycan receptors such as fibroblast growth factor and transforming growth factor-beta, and the other suggests that mahogany itself is a signalling receptor.
129.
Eukaryotic signalling domain homologues in archaea and bacteria. Ancient ancestry and horizontal gene transfer.
Ponting CP, Aravind L, Schultz J, Bork P, Koonin EV
1999 Jun 18; 289(4): 729-45. PubMed: 10369758.
Abstract + PDFPhyletic distributions of eukaryotic signalling domains were studied using recently developed sensitive methods for protein sequence analysis, with an emphasis on the detection and accurate enumeration of homologues in bacteria and archaea. A major difference was found between the distributions of enzyme families that are typically found in all three divisions of cellular life and non-enzymatic domain families that are usually eukaryote-specific. Previously undetected bacterial homologues were identified for# plant pathogenesis-related proteins, Pad1, von Willebrand factor type A, src homology 3 and YWTD repeat-containing domains. Comparisons of the domain distributions in eukaryotes and prokaryotes enabled distinctions to be made between the domains originating prior to the last common ancestor of all known life forms and those apparently originating as consequences of horizontal gene transfer events. A number of transfers of signalling domains from eukaryotes to bacteria were confidently identified, in contrast to only a single case of apparent transfer from eukaryotes to archaea.
128.
No Sec7-homology domain in guanine-nucleotide-exchange factors that act on Ras and Rho.
Ponting CP, Bork P, Schultz J, Aravind L
1999 May; 24(5): 177-8. PubMed: 10322430.
PDF126.
SMART: identification and annotation of domains from signalling and extracellular protein sequences.
1999 Jan 1; 27(1): 229-32. PubMed: 9847187.
Abstract + PDFSMART is a simple modular architecture research tool and database that provides domain identification and annotation on the WWW (http://coot.embl-heidelberg.de/SMART). The tool compares query sequences with its databases of domain sequences and multiple alignments whilst concurrently identifying compositionally biased regions such as signal peptide, transmembrane and coiled coil segments. Annotated and unannotated regions of the sequence can be used as queries in searches of sequence databases. The SMART alignment collection represents more than 250 signalling and extracellular domains. Each alignment is curated to assign appropriate domain boundaries and to ensure its quality. In addition, each domain is annotated extensively with respect to cellular localisation, species distribution, functional class, tertiary structure and functionally important residues.
125.
Solution structure of the receptor tyrosine kinase EphB2 SAM domain and identification of two distinct homotypic interaction sites.
Smalla M, Schmieder P, Kelly M, Ter Laak A, Krause G, Ball L, Wahl M, Bork P, Oschkinat H
1999 Oct; 8(10): 1954-61. PubMed: 10548040.
Abstract + PDFThe sterile alpha motif (SAM) is a protein interaction domain of around 70 amino acids present predominantly in the N- and C-termini of more than 60 diverse proteins that participate in signal transduction and transcriptional repression. SAM domains have been shown to homo- and hetero-oligomerize and to mediate specific protein-protein interactions. A highly conserved subclass of SAM domains is present at the intracellular C-terminus of more than 40 Eph receptor tyrosine kinases that are involved in the control of axonal pathfinding upon ephrin-induced oligomerization and activation in the event of cell-cell contacts. These SAM domains appear to participate in downstream signaling events via interactions with cytosolic proteins. We determined the solution structure of the EphB2 receptor SAM domain and studied its association behavior. The structure consists of five helices forming a compact structure without binding pockets or exposed conserved aromatic residues. Concentration-dependent chemical shift changes of NMR signals reveal two distinct well-separated areas on the domains' surface sensitive to the formation of homotypic oligomers in solution. These findings are supported by analytical ultracentrifugation studies. The conserved Tyr932, which was reported to be essential for the interaction with SH2 domains after phosphorylation, is buried in the hydrophobic core of the structure. The weak capability of the isolated EphB2 receptor SAM domain to form oligomers is supposed to be relevant in vivo when the driving force of ligand binding induces receptor oligomerization. A formation of SAM tetramers is thought to provide an appropriate contact area for the binding of a low-molecular-weight phosphotyrosine phosphatase and to initiate further downstream responses.
124.
Genome phylogeny based on gene content.
Abstract + PDFSpecies phylogenies derived from comparisons of single genes are rarely consistent with each other, due to horizontal gene transfer, unrecognized paralogy and highly variable rates of evolution. The advent of completely sequenced genomes allows the construction of a phylogeny that is less sensitive to such inconsistencies and more representative of whole-genomes than are single-gene trees. Here, we present a distance-based phylogeny constructed on the basis of gene content, rather than on sequence identity, of 13 completely sequenced genomes of unicellular species. The similarity between two species is defined as the number of genes that they have in common divided by their total number of genes. In this type of phylogenetic analysis, evolutionary distance can be interpreted in terms of evolutionary events such as the acquisition and loss of genes, whereas the underlying properties (the gene content) can be interpreted in terms of function. As such, it takes a position intermediate to phylogenies based on single genes and phylogenies based on phenotypic characteristics. Although our comprehensive genome phylogeny is independent of phylogenies based on the level of sequence identity of individual genes, it correlates with the standard reference of prokarytic phylogeny based on sequence similarity of 16s rRNA. Thus, shared gene content between genomes is quantitatively determined by phylogeny, rather than by phenotype, and horizontal gene transfer has only a limited role in determining the gene content of genomes.
123.
Prediction of nonsynonymous single nucleotide polymorphisms in human disease-associated genes.
1999 Nov; 77(11): 754-60. PubMed: 10619435.
Abstract + PDFAnalysis of human genetic variation can shed light on the problem of the genetic basis of complex disorders. Nonsynonymous single nucleotide polymorphisms (SNPs), which affect the amino acid sequence of proteins, are believed to be the most frequent type of variation associated with the respective disease phenotype. Complete enumeration of nonsynonymous SNPs in the candidate genes will enable further association studies on panels of affected and unaffected individuals. Experimental detection of SNPs requires implementation of expensive technologies and is still far from being routine. Alternatively, SNPs can be identified by computational analysis of a publicly available expressed sequence tag (EST) database following experimental verification. We performed in silico analysis of amino acid variation for 471 of proteins with a documented history of experimental variation studies and with confirmed association with human diseases. This allowed us to evaluate the level of completeness of the current knowledge of nonsynonymous SNPs in well studied, medically relevant genes and to estimate the proportion of new variants which can be added with the help of computer-aided mining in EST databases. Our results suggest that approx. 50% of frequent nonsynonymous variants are already stored in public databases. Computational methods based on the scan of an EST database can add significantly to the current knowledge, but they are greatly limited by the size of EST databases and the nonuniform coverage of genes by ESTs. Nevertheless, a considerable number of new candidate nonsynonymous SNPs in genes of medical interest were found by EST screening procedure.
1998 24 publication(s).
122.
Automated Pair-wise Comparisons of Microbial Genomes.
Bansal AK, Bork P, Stuckey P
1998; 9: 1-23. PID: 347.
PDF121.
Merging extracellular domains: fold prediction for laminin G-like and amino-terminal thrombospondin-like modules based on homology to pentraxins.
Beckmann G, Hanke J, Bork P, Reich JG
1998 Feb 6; 275(5): 725-30. PubMed: 9480764.
Abstract + PDFUsing a new method for construction and database searches of sequence consensus strings, we have identified a new superfamily of protein modules comprising laminin G, thrombospondin N and the pentraxin families. The conserved patterns correspond mainly to hydrophobic core residues located in central beta strands of the known three-dimensional structures of two pentraxins, the human C-reactive protein and the serum amyloid P-component. Thus, we predict a similar jellyroll fold for all members of this superfamily. In addition, the conservation of two exposed aspartate residues in the majority of superfamily members suggests hitherto unrecognised functional sites.
120.
Predicting function: from genes to genomes and back.
1998 Nov 6; 283(4): 707-25. PubMed: 9790834.
Abstract + PDFPredicting function from sequence using computational tools is a highly complicated procedure that is generally done for each gene individually. This review focuses on the added value that is provided by completely sequenced genomes in function prediction. Various levels of sequence annotation and function prediction are discussed, ranging from genomic sequence to that of complex cellular processes. Protein function is currently best described in the context of molecular interactions. In the near future it will be possible to predict protein function in the context of higher order processes such as the regulation of gene expression, metabolic pathways and signalling cascades. The analysis of such higher levels of function description uses, besides the information from completely sequenced genomes, also the additional information from proteomics and expression data. The final goal will be to elucidate the mapping between genotype and phenotype.
119.
Characterization of targeting domains by sequence analysis: glycogen-binding domains in protein phosphatases.
1998 Feb; 76(2): 77-9. PubMed: 9500672.
PDF118.
Sequences and Topology.
Deriving biological knowledge from genomic sequence. (editorial overview)
Bork P, Eisenberg D
1998; 8: 331-332. PID: 348.
PDF117.
Predicting functions from protein sequences--where are the bottlenecks?
Bork P, Koonin EV
Abstract + PDFThe exponential growth of sequence data does not necessarily lead to an increase in knowledge about the functions of genes and their products. Prediction of function using comparative sequence analysis is extremely powerful but, if not performed appropriately, may also lead to the creation and propagation of assignment errors. While current homology detection methods can cope with the data flow, the identification, verification and annotation of functional features need to be drastically improved.
116.
Frame: detection of genomic sequencing errors.
Brown NP, Sander C, Bork P
1998; 14(4): 367-71. PubMed: 9632832.
Abstract + PDFMOTIVATION: The underlying error rate for genomic sequencing sometimes results in the introduction of artificial frameshifts and in-frame stop codons into putative protein encoding genes. Severe errors are then introduced into the inferred transcripts through mis-translation or premature termination. RESULTS: We describe a system for screening segments of DNA for frameshift and in-frame stop errors in coding regions. The method is based on homology matching using blastx to compare all six reading frames of the query nucleotide sequence against selected protein sequence databases. Fragments of protein matching neighbouring regions of the query DNA are united and extended laterally to define candidate open reading frames, within which, frameshifts and stops are identified. Suitable targets include prokaryotic or other intron-free genomic sequence and complementary DNAs. As an example of its use, we report here two frameshifted ORFs that deviate from the original TIGR sequence annotations for the recently released Helicobacter pylori genome. AVAILABILITY: The tool is accessible via the URL http://www.sander.ebi.ac.uk/frame/. CONTACT: brown@ebi.ac.uk.
115.
Homology-based gene prediction using neural nets.
Cai YD, Bork P
1998 Dec 15; 265(2): 269-74. PubMed: 9882402.
Abstract + PDFWe have developed and implemented a method for computational gene identification called GIN (gene identification using neural nets and homology information) that has been particularly designed to avoid false positive predictions. It thus predicts 55% of all genes tested correctly, has a specificity of 99%, but also has an overall accuracy of 92% on a benchmark set of 570 vertebrate genes constructed by Burset and Guigo. The method combines homology searches in protein and expressed sequence tag databases with several neural networks designed to recognize start codons, Poly(A) signals, stop codons, and splice sites. Predicted exons are assembled into genes using a homology-based scoring function. GIN is able to recognize multiple genes within genomic DNA as demonstrated by the identification of a globin gene (gamma-globin-1(G)) that has not been annotated as a coding region in the widely used the test set of Burset and Guigo. Furthermore, GIN identifies more than 107 other protein hits in noncoding regions and classifies them into possible pseudogenes or splice variants.
114.
Systematic genomic screening and analysis of mRNA in untranslated regions and mRNA precursors: combining experimental and computational approaches.
Dandekar T, Beyer K, Bork P, Kenealy MR, Pantopoulos K, Hentze M, Sonntag-Buck V, Flouriot G, Gannon F, Schreiber S
1998; 14(3): 271-8. PubMed: 9614270.
Abstract + PDFMOTIVATION: The untranslated regions (UTRs) of mRNA upstream (5'UTR) and downstream (3'UTR) of the open reading frame, as well as the mRNA precursor, carry important regulatory sequences. To reveal unidentified regulatory signals, we combine information from experiments with computational approaches. Depending on available knowledge, three different strategies are employed. RESULTS: Searching with a consensus template, new RNAs with regulatory RNA elements can be identified in genomic screens. By this approach, we identify new candidate regulatory motifs resembling iron-responsive elements in the 5'UTRs of HemA, FepB and FrdB mRNA from Escherichia coli. If an RNA element is not yet defined, it may be analyzed by combining results from SELEX (selective enrichment of ligands by exponential amplification) and a search of databases from RNA or genomic sequences. A cleavage stimulating factor (CstF) binding element 3 of the polyadenylation site in the mRNA precursor serves as a test example. Alternatively, the regulatory RNA element may be found by studying different RNA foldings and their correlation with simple experimental tests. We delineate a novel instability element in the 3'UTR of the estrogen receptor mRNA in this way. AVAILABILITY: Strategy, methods and programs are available on request from T.Dandekar. CONTACT: dandekar@embl-heidelberg.de
113.
Conservation of gene order: a fingerprint of proteins that physically interact.
1998 Sep; 23(9): 324-8. PubMed: 9787636.
Abstract + PDFA systematic comparison of nine bacterial and archaeal genomes reveals a low level of gene-order (and operon architecture) conservation. Nevertheless, a number of gene pairs are conserved. The proteins encoded by conserved gene pairs appear to interact physically. This observation can therefore be used to predict functions of, and interactions between, prokaryotic gene products.
112.
Protein annotation: detective work for function prediction.
Doerks T, Bairoch A, Bork P
1998 Jun; 14(6): 248-50. PubMed: 9635409.
PDF111.
Sequence properties of GPI-anchored proteins near the omega-site: constraints for the polypeptide binding site of the putative transamidase.
1998 Dec; 11(12): 1155-61. PubMed: 9930665.
AbstractGlycosylphosphatidylinositol (GPI) anchoring is a common post-translational modification of extracellular eukaryotic proteins. Attachment of the GPI moiety to the carboxyl terminus (omega-site) of the polypeptide occurs after proteolytic cleavage of a C-terminal propeptide. In this work, the sequence pattern for GPI-modification was analyzed in terms of physical amino acid properties based on a database analysis of annotated proprotein sequences. In addition to a refinement of previously described sequence signals, we report conserved sequence properties in the regions omega - 11...omega - 1 and omega + 4...omega + 5. We present statistical evidence for volume-compensating residue exchanges with respect to the positions omega - 1...omega + 2. Differences between protozoan and metazoan GPI-modification motifs consist mainly in variations of preferences to amino acid types at the positions near the omega-site and in the overall motif length. The variations of polypeptide substrates are exploited to suggest a model of the polypeptide binding site of the putative transamidase, the enzyme catalyzing the GPI-modification. The volume of the active site cleft accommodating the four residues omega - 1...omega + 2 appears to be approximately 540 A3.
110.
Sequence and Structure of Proteins.
Eisenhaber F, Bork P
In: Recombinant proteins, monoclonal antibodies and theraeutic genes (series Biotechnology, 2nd. Edition). (Rehm, H.-J. Reed, G+A. Mountain, U. Ney and D. Schomburg)5a pp.43-86. BID: 11.
Publisher: Wiley-VCH Weinheim
PDF109.
Wanted: subcellular localization of proteins based on sequence.
Eisenhaber F, Bork P
1998 Apr; 8(4): 169-70. PubMed: 9695832.
PDF108.
Measuring genome evolution.
Huynen MA, Bork P
1998 May 26; 95(11): 5849-56. PubMed: 9600883.
Abstract + PDFThe determination of complete genome sequences provides us with an opportunity to describe and analyze evolution at the comprehensive level of genomes. Here we compare nine genomes with respect to their protein coding genes at two levels: (i) we compare genomes as "bags of genes" and measure the fraction of orthologs shared between genomes and (ii) we quantify correlations between genes with respect to their relative positions in genomes. Distances between the genomes are related to their divergence times, measured as the number of amino acid substitutions per site in a set of 34 orthologous genes that are shared among all the genomes compared. We establish a hierarchy of rates at which genomes have changed during evolution. Protein sequence identity is the most conserved, followed by the complement of genes within the genome. Next is the degree of conservation of the order of genes, whereas gene regulation appears to evolve at the highest rate. Finally, we show that some genomes are more highly organized than others: they show a higher degree of the clustering of genes that have orthologs in other genomes.
107.
Differential genome analysis applied to the species-specific features of Helicobacter pylori.
Abstract + PDFWe introduce a simple and rapid strategy to identify genes that are responsible for species-specific phenotypes. The genome of a species that has a specific phenotype is compared with at least one, closely related, species that lacks this phenotype. Homologous genes that are shared among the species compared are identified and discarded from the list of candidates for species-specific genes. The process is automated and rapidly yields a small subset of the genome that likely contains genes responsible for the species-specific features. Functions are assigned to the genes, and dubious annotations are filtered out. Information is extracted not only from the presence of genes, but also from their absence with respect to known phenotypes. We have applied the technique to identify a set of species-specific genes in Helicobacter pylori by comparing it with its closest relatives for which complete genome sequences are available, Haemophilus influenzae and Escherichia coli. Of the genes of this set for which functional features can be obtained, a large fraction (63%, 123 proteins) is (potentially) involved in H. pylori's interaction with its host. We hypothesize that a family of outer membrane proteins is critical for the ability of H. pylori to colonize host cells in highly acidic environments.
106.
Homology-based fold predictions for Mycoplasma genitalium proteins.
1998 Jul 17; 280(3): 323-6. PubMed: 9665839.
Abstract + PDFHomology search techniques based on the iterative PSI-BLAST method in combination with various filters for low sequence complexity are applied to assign folds to all Mycoplasma genitalium proteins. The resulting procedure (implemented as a web server) is able to predict at least one domain in 37% of these proteins automatically, with an estimated accuracy higher than 98%. Taking structural features such as coiled coil or transmembrane regions aside, folds can be assigned to more than half of the globular proteins in a bacterium just by iterative sequence comparison.
105.
Conformational stability studies of the pleckstrin DEP domain: definition of the domain boundaries.
Kharrat A, Millevoi S, Baraldi E, Ponting CP, Bork P, Pastore A
1998 Jun 11; 1385(1): 157-64. PubMed: 9630596.
Abstract + PDFPleckstrin is the major substrate of protein kinase C in platelets. It contains at its N- and C-termini two pleckstrin homology (PH) domains which have been proposed to mediate protein-protein and protein-lipid interactions. A new module, called DEP, has recently been identified by sequence analysis in the central region of pleckstrin. In order to study this module, several recombinant polypeptides corresponding to the DEP module and N- and C-termini extended forms have been expressed. Using circular dichroism (CD) and nuclear magnetic resonance (NMR) techniques, the domain boundaries have been determined that yield a soluble and folded pleckstrin DEP domain. This comprises 93 amino acids with an alpha/beta fold in agreement with secondary structure predictions. Stability studies indicate that the regions surrounding the DEP domain do not contribute to its stability suggesting that the phosphorylation sites at S113, T114 and S117 are in an unstructured region. Identification of the regions of pleckstrin that are folded shall facilitate determination of its structure and function.
104.
Evolution of new protein function: recombinational enhancer Fis originated by horizontal gene transfer from the transcriptional regulator NtrC.
Morett E, Bork P
Abstract + PDFNew protein function is thought to evolve mostly by gene duplication and divergence. Here we present phylogenetic evidence that the multifunctional protein Fis of the gamma proteobacterial species derived from the COOH-terminal domain of an ancestral alpha proteobacterial NtrC transcriptional regulatory protein. All of the known enterobacterial fis genes are preceded by an open reading frame, named yhdG, that is highly similar to nifR3, a gene that forms an operon with ntrC in several alpha proteobacterial species. Thus, we propose that yhdG and fis were acquired by a lineage ancestral to the gamma proteobacteria in a single horizontal gene transfer event, and later diverged to their present functions.
103.
SMART, a simple modular architecture research tool: identification of signaling domains.
1998 May 26; 95(11): 5857-64. PubMed: 9600884.
Abstract + PDFAccurate multiple alignments of 86 domains that occur in signaling proteins have been constructed and used to provide a Web-based tool (SMART: simple modular architecture research tool) that allows rapid identification and annotation of signaling domain sequences. The majority of signaling proteins are multidomain in character with a considerable variety of domain combinations known. Comparison with established databases showed that 25% of our domain set could not be deduced from SwissProt and 41% could not be annotated by Pfam. SMART is able to determine the modular architectures of single sequences or genomes; application to the entire yeast genome revealed that at least 6.7% of its genes contain one or more signaling domains, approximately 350 greater than previously annotated. The process of constructing SMART predicted (i) novel domain homologues in unexpected locations such as band 4.1-homologous domains in focal adhesion kinases; (ii) previously unknown domain families, including a citron-homology domain; (iii) putative functions of domain families after identification of additional family members, for example, a ubiquitin-binding role for ubiquitin-associated domains (UBA); (iv) cellular roles for proteins, such predicted DEATH domains in netrin receptors further implicating these molecules in axonal guidance; (v) signaling domains in known disease genes such as SPRY domains in both marenostrin/pyrin and Midline 1; (vi) domains in unexpected phylogenetic contexts such as diacylglycerol kinase homologues in yeast and bacteria; and (vii) likely protein misclassifications exemplified by a predicted pleckstrin homology domain in a Candida albicans protein, previously described as an integrin.
102.
Elementary Modes Analysis Illustrated with Human Red Cell Metabolism.
In: BioThermoKinetics in the Post Genomic Era. (C. Larsson, I.-L. Pahlman and L. Gustafsson, eds.) pp.332-339. BID: 12.
Publisher: Chalmers, Goeteborg
101.
Differential gene expression in mammary carcinoma cell lines: identification of DRIM, a new gene down-regulated in metastasis.
Schwirzke M, Gnirke A, Bork P, Tarin D, Weidle UH
1998 May-Jun; 18(3A): 1409-21. PubMed: 9673349.
Abstract + PDFDifferential display technique was applied to a pair of cell lines derived from human breast carcinoma cell line MDA-MB 435 with metastatic and non-metastatic properties in the nude mouse system, with the objective to isolate genes involved in metastasis. DRIM (Down-Regulated In Metastasis) was the only gene found to be differentially expressed in this system. DRIM encodes a protein comprising 2785 amino acids with significant homology to a protein in yeast and C. elegans. The protein contains a conserved positively charged tail and several HEAT repeats, designated after four functionally characterized proteins in which the repeat was detected. Most of the hydrophobic regions of DRIM can be assigned to HEAT repeats. Expression of DRIM at the RNA level was investigated in several normal tissues and tumor cell lines.
100.
Identical variant TSG101 transcripts in soft tissue sarcomas and various non-neoplastic tissues.
Willeke F, Ridder R, Bork P, Klaes R, Mechtersheimer G, Schwarzbach M, Zimmer D, Kloor M, Lehnert T, Herfarth C, von Knebel Doeberitz M
1998 Dec; 23(4): 195-200. PubMed: 9869447.
Abstract + PDFInactivation of the TSG101 gene was recently shown to induce malignant transformation of NIH/3T3 fibroblasts. Abnormal TSG101 transcription profiles were observed in various human cancers, and large intragenic deletions of the TSG101 gene were reported for a series of human breast cancer specimens, pointing to a potential tumor-suppressive activity of TSG101. However, subsequent more detailed studies on a large panel of breast carcinoma samples did not confirm the tumor-associated genomic deletions. Here we analyzed the transcription patterns of the TSG101 gene in soft-tissue sarcomas and non-neoplastic human tissues. Forty-five of 71 soft tissue sarcoma samples (63%) displayed variant transcripts; however, identical aberrant transcripts were also detected in seven of 15 non-neoplastic control tissues. Restriction fragment length polymorphism analysis of the TSG101 gene excluded major genomic rearrangements in the soft tissue sarcoma samples. Northern blot analysis revealed a very low abundance of variant transcripts as compared with the wild-type TSG101 transcript. These data point to aberrant splicing of the TSG101 mRNA in normal and transformed human mesenchymal tissues rather than tumor specific alterations of the TSG101 gene. In summary, this analyses does not support a pathogenic role for altered TSG101 expression in human soft tissue sarcomas.
99.
Towards detection of orthologues in sequence databases.
Yuan YP, Eulenstein O, Vingron M, Bork P
1998; 14(3): 285-9. PubMed: 9614272.
Abstract + PDFMOTIVATION: Numerous homologous sequences from diverse species can be retrieved from databases using programs such as BLAST. However, due to multigene families, evolutionary relationship often cannot be easily determined and proper functional assignment becomes difficult. Thus, discrimination between orthologues and paralogues within BLAST output lists of homologous sequences becomes more and more important. RESULT: We therefore developed a method that attempts to construct a reconciled tree from a gene tree of selected sequences and its corresponding phylogenetic tree of the species involved (species tree). An interface on the Web is developed to enable users to analyse the BLAST result. BLAST outputs are parsed and, for the selected sequences, multiple alignments are constructed either globally or for local regions. Bootstrapped trees are returned and compared with the expected species tree. In cases of discrepancies, gene duplications are assumed and a reconciled tree is computed. The reconciled tree shows probable orthologues and paralogues as predicted.
1997 16 publication(s).
98.
Bioinformatics and molecular medicine--introduction and call for papers.
Bork P
1997 Jan; 75(1): 3-4. PubMed: 9020378.
PDF96.
A superfamily of conserved domains in DNA damage-responsive cell cycle checkpoint proteins.
Bork P, Hofmann K, Bucher P, Neuwald AF, Altschul SF, Koonin EV
Abstract + PDFComputer analysis of a conserved domain, BRCT, first described at the carboxyl terminus of the breast cancer protein BRCA1, a p53 binding protein (53BP1), and the yeast cell cycle checkpoint protein RAD9 revealed a large superfamily of domains that occur predominantly in proteins involved in cell cycle checkpoint functions responsive to DNA damage. The BRCT domain consists of approximately 95 amino acid residues and occurs as a tandem repeat at the carboxyl terminus of numerous proteins, but has been observed also as a tandem repeat at the amino terminus or as a single copy. The BRCT superfamily presently includes approximately 40 nonorthologous proteins, namely, BRCA1, 53BP1, and RAD9; a protein family that consists of the fission yeast replication checkpoint protein Rad4, the oncoprotein ECT2, the DNA repair protein XRCC1, and yeast DNA polymerase subunit DPB11; DNA binding enzymes such as terminal deoxynucleotidyltransferases, deoxycytidyl transferase involved in DNA repair, and DNA-ligases III and IV; yeast multifunctional transcription factor RAP1; and several uncharacterized gene products. Another previously described domain that is shared by bacterial NAD-dependent DNA-ligases, the large subunits of eukaryotic replication factor C, and poly(ADP-ribose) polymerases appears to be a distinct version of the BRCT domain. The retinoblastoma protein (a universal tumor suppressor) and related proteins may contain a distant relative of the BRCT domain. Despite the functional diversity of all these proteins, participation in DNA damage-responsive checkpoints appears to be a unifying theme. Thus, the BRCT domain is likely to perform critical, yet uncharacterized, functions in the cell cycle control of organisms from bacteria to humans. The carboxyterminal BRCT domain of BRCA1 corresponds precisely to the recently identified minimal transcription activation domain of this protein, indicating one such function.
95.
Cytoplasmic signalling domains: the next generation.
Bork P, Schultz J, Ponting CP
1997 Aug; 22(8): 296-8. PubMed: 9270302.
Abstract + PDFSince the late 1980s, when Src-homology SH2 and SH3 domains were identified, the repertoire of non-catalytic signalling domains has increased to number over 30. As it is expected that further regulatory domains shall be found, unravelling the complex network of their interactions remains an on-going challenge.
94.
Genome maps 8. Building gene families. Wall chart.
Green EA, Pietrokovski S, Henikoff S, Bork P, Attwood T, Hood L, Bairoch A
93.
A novel class of RanGTP binding proteins.
Görlich D, Dabrowski M, Bischoff FR, Kutay U, Bork P, Hartmann E, Prehn S, Izaurralde E
1997 Jul 14; 138(1): 65-80. PubMed: 9214382.
Abstract + PDFThe importin-alpha/beta complex and the GTPase Ran mediate nuclear import of proteins with a classical nuclear localization signal. Although Ran has been implicated also in a variety of other processes, such as cell cycle progression, a direct function of Ran has so far only been demonstrated for importin-mediated nuclear import. We have now identified an entire class of approximately 20 potential Ran targets that share a sequence motif related to the Ran-binding site of importin-beta. We have confirmed specific RanGTP binding for some of them, namely for two novel factors, RanBP7 and RanBP8, for CAS, Pse1p, and Msn5p, and for the cell cycle regulator Cse1p from Saccharomyces cerevisiae. We have studied RanBP7 in more detail. Similar to importin-beta, it prevents the activation of Ran's GTPase by RanGAP1 and inhibits nucleotide exchange on RanGTP. RanBP7 binds directly to nuclear pore complexes where it competes for binding sites with importin-beta, transportin, and apparently also with the mediators of mRNA and U snRNA export. Furthermore, we provide evidence for a Ran-dependent transport cycle of RanBP7 and demonstrate that RanBP7 can cross the nuclear envelope rapidly and in both directions. On the basis of these results, we propose that RanBP7 might represent a nuclear transport factor that carries an as yet unknown cargo, which could apply as well for this entire class of related RanGTP-binding proteins.
92.
On the classification and evolution of protein modules.
Hegyi H, Bork P
1997 Jul; 16(5): 545-51. PubMed: 9246642.
Abstract + PDFOur efforts to classify the functional units of many proteins, the modules, are reviewed. The data from the sequencing projects for various model organisms are extremely helpful in deducing the evolution of proteins and modules. For example, a dramatic increase of modular proteins can be observed from yeast to C. elegans in accordance with new protein functions that had to be introduced in multicellular organisms. Our sequence characterization of modules relies on sensitive similarity search algorithms and the collection of multiple sequence alignments for each module. To trace the evolution of modules and to further automate the classification, we have developed a sequence and a module alerting system that checks newly arriving sequence data for the presence of already classified modules. Using these systems, we were able to identify an unexpected similarity between extracellular C1Q modules with bacterial proteins.
91.
The Sequence Alerting Server--a new WEB server.
1997 Dec; 13(6): 619-20. PubMed: 9475991.
Abstract + PDFA Sequence Alerting Server with a WWW interface is described which informs users with query sequences in database searches about new entries in protein databases related to their query. AVAILABILITY: The server address is http://www.bork.embl-heidelberg.de/alerting/.
90.
Gene families: the taxonomy of protein paralogs and chimeras.
Henikoff S, Greene EA, Pietrokovski S, Bork P, Attwood TK, Hood L
Abstract + PDFAncient duplications and rearrangements of protein-coding segments have resulted in complex gene family relationships. Duplications can be tandem or dispersed and can involve entire coding regions or modules that correspond to folded protein domains. As a result, gene products may acquire new specificities, altered recognition properties, or modified functions. Extreme proliferation of some families within an organism, perhaps at the expense of other families, may correspond to functional innovations during evolution. The underlying processes are still at work, and the large fraction of human and other genomes consisting of transposable elements may be a manifestation of the evolutionary benefits of genomic flexibility.
88.
A putative nucleic acid-binding domain in Bloom's and Werner's syndrome helicases.
Morozov VM, Mushegian AR, Koonin EV, Bork P
1997 Nov; 22(11): 417-8. PubMed: 9397680.
PDF87.
Positionally cloned human disease genes: patterns of evolutionary conservation and functional motifs.
Mushegian AR, Bassett DE, Boguski MS, Bork P, Koonin EV
1997 May 27; 94(11): 5831-6. PubMed: 9159160.
Abstract + PDFPositional cloning has already produced the sequences of more than 70 human genes associated with specific diseases. In addition to their medical importance, these genes are of interest as a set of human genes isolated solely on the basis of the phenotypic effect of the respective mutations. We analyzed the protein sequences encoded by the positionally cloned disease genes using an iterative strategy combining several sensitive computer methods. Comparisons to complete sequence databases and to separate databases of nematode, yeast, and bacterial proteins showed that for most of the disease gene products, statistically significant sequence similarities are detectable in each of the model organisms. Only the nematode genome encodes apparent orthologs with conserved domain architecture for the majority of the disease genes. In yeast and bacterial homologs, domain organization is typically not conserved, and sequence similarity is limited to individual domains. Generally, human genes complement mutations only in orthologous yeast genes. Most of the positionally cloned genes encode large proteins with several globular and nonglobular domains, the functions of some or all of which are not known. We detected conserved domains and motifs not described previously in a number of proteins encoded by disease genes and predicted functions for some of them. These predictions include an ATP-binding domain in the product of hereditary nonpolyposis colon cancer gene (a MutL homolog), which is conserved in the HS90 family of chaperone proteins, type II DNA topoisomerases, and histidine kinases, and a nuclease domain homologous to bacterial RNase D and the 3'-5' exonuclease domain of DNA polymerase I in the Werner syndrome gene product.
86.
SPRY domains in ryanodine receptors (Ca(2+)-release channels).
1997 Jun; 22(6): 193-4. PubMed: 9204703.
PDF85.
The breast cancer gene product TSG101: a regulator of ubiquitination?
Ponting CP, Cai YD, Bork P
1997 Jul; 75(7): 467-9. PubMed: 9253709.
Abstract + PDFSequence analysis is a powerful tool to obtain structural and functional information about genes and their products. Here we show that TSG101, a gene subjected to somatic mutations in breast cancer, contains an amino terminal domain that is a homologue of ubiquitin conjugating enzymes (UBCs) and not, as previously proposed, DNA-binding domains. As the UBC active site residue is replaced in the TSG101 sequence in a similar manner to several other members of the UBC family, we propose a role for TSG101 in regulating the ubiquitination of short-lived gene products.
84.
SAM as a protein interaction domain involved in developmental regulation.
Schultz J, Ponting CP, Hofmann K, Bork P
1997 Jan; 6(1): 249-53. PubMed: 9007998.
Abstract + PDFMore than 60 previously undetected SAM domain-containing proteins have been identified using profile searching methods. Among these are over 40 EPH-related receptor tyrosine kinases (RPTK), Drosophila bicaudal-C, a p53 from Loligo forbesi, and diacyglycerol-kinase isoform delta. This extended dataset suggests that SAM is an evolutionary conserved protein binding domain that is involved in the regulation of numerous developmental processes among diverse eukaryotes. A conserved tyrosine in the SAM sequences of the EPH related RPTKs is likely to mediate cell-cell initiated signal transduction via the binding of SH2 containing proteins to phosphotyrosine.
1996 21 publication(s).
82.
On exon shuffling and other mechanisms of domain rearrangements.
Bork P
1996; 15: 311-12. PID: 370.
PDF79.
Go hunting in sequence databases but watch out for the traps.
Bork P, Bairoch A
1996 Oct; 12(10): 425-7. PubMed: 8909140.
PDF77.
The protein phosphatase 2C (PP2C) superfamily: detection of bacterial homologues.
1996 Jul; 5(7): 1421-5. PubMed: 8819174.
Abstract + PDFA thorough sequence analysis of the various members of the eukaryotic protein serine/threonine phosphatase 2C (PP2C) family revealed the conservation of 11 motifs. These motifs could be identified in numerous other sequences, including fungal adenylate cyclases that are predicted to contain a functionally active PP2C domain, and a family of prokaryotic serine/threonine phosphatases including SpoIIE. Phylogenetic analysis of all the proteins indicates a widespread sequence family for which a considerable number of isoenzymes can be inferred.
76.
Structure and distribution of modules in extracellular proteins.
Bork P, Downing AK, Kieffer B, Campbell ID
1996 May; 29(2): 119-67. PubMed: 8870072.
PDF74.
Protein sequence motifs.
Bork P, Koonin EV
1996 Jun; 6(3): 366-76. PubMed: 8804823.
Abstract + PDFProtein sequence motifs are signatures of protein families and can often be used as tools for the prediction of protein function. The generalization and modification of already known motifs are becoming major trends in the literature, even though new motifs are still being discovered at an approximately linear rate. The emphasis of motif analysis appears to be shifting from metabolic enzymes, in which motifs are associated with catalytic functions and thus often readily recognizable, to structural and regulatory proteins, which contain more divergent motifs. The consideration of structural information increasingly contributes to the identification of motifs and their sensitivity. Genome sequencing provides the basis for a systematic analysis of all motifs that are present in a particular organism. A systematically derived motif database is therefore feasible, allowing the classification of the majority of the newly appearing protein sequences into known families.
73.
Friedreich's ataxia protein: phylogenetic evidence for mitochondrial dysfunction.
Gibson TJ, Koonin EV, Musco G, Pastore A, Bork P
1996 Nov; 19(11): 465-8. PubMed: 8931268.
Abstract + PDFFriedreich's ataxia is the most common inherited spinocerebellar ataxia. A decade of linkage and physical mapping studies have culminated in the identification of the Friedreich's ataxia gene. The presence of homologues in purple bacterial genomes, but not in other bacteria, allows us to infer a mitochondrial location for frataxin (Friedreich's ataxia protein) on the basis of bacterial phylogeny. Frataxin possesses a non-globular N-terminus domain providing a candidate mitochondrial targeting peptide. Clues to the function of frataxin are provided by the mitochondrial location, a clinically similar ataxia with vitamin E deficiency, and certain neuropathies with mitochondrial DNA instability caused by mutations in nuclear genes.
72.
Self-organizing hierarchic networks for pattern recognition in protein sequence.
Hanke J, Beckmann G, Bork P, Reich JG
1996 Jan; 5(1): 72-82. PubMed: 8771198.
Abstract + PDFWe present a method based on hierarchical self-organizing maps (SOMs) for recognizing patterns in protein sequences. The method is fully automatic, does not require prealigned sequences, is insensitive to redundancy in the training set, and works surprisingly well even with small learning sets. Because it uses unsupervised neural networks, it is able to extract patterns that are not present in all of the unaligned sequences of the learning set. The identification of these patterns in sequence databases is sensitive and efficient. The procedure comprises three main training stages. In the first stage, one SOM is trained to extract common features from the set of unaligned learning sequences. A feature is a number of ungapped sequence segments (usually 4-16 residues long) that are similar to segments in most of the sequences of the learning set according to an initial similarity matrix. In the second training stage, the recognition of each individual feature is refined by selecting an optimal weighting matrix out of a variety of existing amino acid similarity matrices. In a third stage of the SOM procedure, the position of the features in the individual sequences is learned. This allows for variants with feature repeats and feature shuffling. The procedure has been successfully applied to a number of notoriously difficult cases with distinct recognition problems: helix-turn-helix motifs in DNA-binding proteins, the CUB domain of developmentally regulated proteins, and the superfamily of ribokinases. A comparison with the established database search procedure PROFILE (and with several others) led to the conclusion that the new automatic method performs satisfactorily.
71.
On the classification of modular proteins.
Henrissat B, Bork P
1996 Sep; 9(9): 725-6. PubMed: 8888136.
PDF69.
Ancient duplication of DNA polymerase inferred from analysis of complete bacterial genomes.
Koonin EV, Bork P
1996 Apr; 21(4): 128-9. PubMed: 8701468.
PDF68.
Non-orthologous gene displacement.
Koonin EV, Mushegian AR, Bork P
1996 Sep; 12(9): 334-6. PubMed: 8855656.
PDF67.
Structural motifs of the PKD1 protein.
Löhning C, Pohlschmidt M, Glücksmann-Kuis MA, Duyk G, Bork P, Schneider MO, Reeders ST, Frischauf AM
1996; 11 Suppl 6: 2-4. PubMed: 9044318.
Abstract + PDFThe complete sequence of the polycystic kidney disease gene (PKD1) and its transcript have been described. The predicted protein is not a member of a previously described gene family, but contains several structural motifs that are present in proteins of known function. Most of these domains are present in the extracellular parts of proteins involved in interactions with other proteins and carbohydrates. The PKD1 gene product also contains potential transmembrane sequences. The molecule is likely to be involved in cell-cell or cell-matrix interactions, which is consistent with the different manifestations of polycystic kidney disease.
66.
Identification and mutation analysis of the complete gene for Chediak-Higashi syndrome.
Nagle DL, Karim MA, Woolf EA, Holmgren L, Bork P, Misumi DJ, McGrail SH, Dussault BJ, Perou CM, Boissy RE, Duyk GM, Spritz RA, Moore KJ
Abstract + PDFChediak-Higashi syndrome (CHS) is a rare, autosomal recessive disorder characterized by hypopigmentation, severe immunologic deficiency with neutropenia and lack of natural killer (NK) cells, a bleeding tendency and neurologic abnormalities. Most patients die in childhood. The CHS hallmark is the occurrence of giant inclusion bodies and organelles in a variety of cell types, and protein sorting defects into these organelles. Similar abnormalities occur in the beige mouse, the proposed model for human CHS. Two groups have recently reported the identification of the beige gene, however the two cDNAs were not at all similar. Here we describe the sequence of a human cDNA homologous to mouse beige, identify pathologic mutations and clarify the discrepancies of the previous reports. Analysis of the CHS polypeptide demonstrates that its modular architecture is similar to the yeast vacuolar sorting protein, VPS15.
65.
Comparison of CD45 extracellular domain sequences from divergent vertebrate species suggests the conservation of three fibronectin type III domains.
Okumura M, Matthews RJ, Robb B, Litman GW, Bork P, Thomas ML
Abstract + PDFMammalian CD45 is a transmembrane protein tyrosine phosphatase expressed by all nucleated cells of hematopoietic origin. In lymphocytes, CD45 is required for Ag-induced signal transduction due to its ability to positively regulate Src family members. The mechanisms by which CD45 function is regulated are unknown. Indeed, the interactions of CD45 extracellular domains are largely undefined. To gain insight into potentially important regions of the extracellular domain, we sought to identify conserved features from divergent species. cDNAs encoding the putative CD45 homologue from Heterodontus francisci (horned shark) were isolated. The cDNA sequence predicts a protein of 1200 amino acids that contains a 452-amino acid extracellular domain, a 22-amino acid transmembrane region, and a 703-amino acid cytoplasmic domain. Alignment searches revealed that the Heterodontus cytoplasmic domain sequence was most identical to mammalian CD45 and a transmembrane protein tyrosine phosphatase sequence identified from chickens, ChPTP lambda. A dendrogram with other transmembrane protein tyrosine phosphatase sequences suggest that the Heterodontus and chicken sequences represents CD45 orthologues for their respective species. Analysis of vertebrate CD45 extracellular domain sequences indicates the conservation of three structural regions: a region containing potential O-linked carbohydrate sites, a cysteine-containing region, and a region containing three fibronectin type III domains. For each vertebrate species, multiple isoforms are generated by alternative splicing of three exons that encode a portion of the region containing potential O-linked glycosylation sites. These studies provide evidence for a conservation in CD45 extracellular domain structure between divergent species and provide a basis for understanding CD45 extracellular domain interactions.
64.
Pleckstrin's repeat performance: a novel domain in G-protein signaling?
Ponting CP, Bork P
1996 Jul; 21(7): 245-6. PubMed: 8755244.
PDF63.
Metabolism and evolution of Haemophilus influenzae deduced from a whole-genome comparison with Escherichia coli.
Tatusov RL, Mushegian AR, Bork P, Brown NP, Hayes WS, Borodovsky M, Rudd KE, Koonin EV
Abstract + PDFBACKGROUND. The 1.83 Megabase (Mb) sequence of the Haemophilus influenzae chromosome, the first completed genome sequence of a cellular life form, has been recently reported. Approximately 75 % of the 4.7 Mb genome sequence of Escherichia coli is also available. The life styles of the two bacteria are very different - H. influenzae is an obligate parasite that lives in human upper respiratory mucosa and can be cultivated only on rich media, whereas E. coli is a saprophyte that can grow on minimal media. A detailed comparison of the protein products encoded by these two genomes is expected to provide valuable insights into bacterial cell physiology and genome evolution. RESULTS. We describe the results of computer analysis of the amino-acid sequences of 1703 putative proteins encoded by the complete genome of H. influenzae. We detected sequence similarity to proteins in current databases for 92 % of the H. influenzae protein sequences, and at least a general functional prediction was possible for 83 %. A comparison of the H. influenzae protein sequences with those of 3010 proteins encoded by the sequenced 75 % of the E. coli genome revealed 1128 pairs of apparent orthologs, with an average of 59 % identity. In contrast to the high similarity between orthologs, the genome organization and the functional repertoire of genes in the two bacteria were remarkably different. The smaller genome size of H. influenzae is explained, to a large extent, by a reduction in the number of paralogous genes. There was no long range colinearity between the E. coli and H. influenzae gene orders, but over 70 % of the orthologous genes were found in short conserved strings, only about half of which were operons in E. coli. Superposition of the H. influenzae enzyme repertoire upon the known E. coli metabolic pathways allowed us to reconstruct similar and alternative pathways in H. influenzae and provides an explanation for the known nutritional requirements. CONCLUSIONS. By comparing proteins encoded by the two bacterial genomes, we have shown that extensive gene shuffling and variation in the extent of gene paralogy are major trends in bacterial evolution; this comparison has also allowed us to deduce crucial aspects of the largely uncharacterized metabolism of H. influenzae.
62.
Identification of residues within the SHC phosphotyrosine binding/phosphotyrosine interaction domain crucial for phosphopeptide interaction.
Yajnik V, Blaikie P, Bork P, Margolis B
1996 Jan 26; 271(4): 1813-6. PubMed: 8567619.
Abstract + PDFShc is an Src homology 2 (SH2) domain protein thought to be an important component of the signaling pathway leading from cell surface receptors to Ras. A new phosphotyrosine interaction (PI) domain (also known as the phosphotyrosine binding (PTB) domain) has been described in the amino terminus of Shc. The Shc PI domain binding specificity is dependent on residues lying amino-terminal to the phosphotyrosine rather than carboxyl-terminal as is seen with SH2 domains. We randomly mutagenized the Shc PTB/PI domain in an effort to identify residues in the domain crucial for interaction with phosphotyrosine-containing peptides. We then screened the mutants for binding to the tyrosine-phosphorylated carboxyl-terminal tail of the epidermal growth factor (EGF) receptor. Most striking were mutations that altered a phenylalanine residue in block 4 of the domain severely impairing PI domain function. This phenylalanine residue is conserved in all but one subfamily of PI domains that have been identified to date. Reconstitution of this phenylalanine mutation into full-length Shc created a protein unable to interact with the EGF receptor in living cells.
1995 12 publication(s).
60.
Divergent evolution of a beta/alpha-barrel subclass: detection of numerous phosphate-binding sites by motif search.
Bork P, Gellerich J, Groth H, Hooft R, Martin F
1995 Feb; 4(2): 268-74. PubMed: 7757015.
Abstract + PDFStudy of the most conserved region in many beta/alpha-barrels, the phosphate-binding site, revealed a sequence motif in a few beta/alpha-barrels with known tertiary structure, namely glycolate oxidase (GOX), cytochrome b2 (Cyb2), tryptophan synthase alpha subunit (TrpA), and the indoleglycerolphosphate synthase (TrpC). Database searches identified this motif in numerous other enzyme families: (1) IMP dehydrogenase (IMPDH) and GMP reductase (GuaC); (2) phosphoribosylformimino-5-aminoimidazol carboxamide ribotide isomerase (HisA) and the cyclase-producing D-erythro-imidazole-glycerolphosphate (HisF) of the histidine biosynthetic pathway; (3) dihydroorotate dehydrogenase (PyrD); (4) glutamate synthase (GltB); (5) ThiE and ThiG involved in the biosynthesis of thiamine as well as related proteins; (6) an uncharacterized open reading frame from Erwinia herbicola; and (7) a glycerol uptake operon antiterminator regulatory protein (GlpP). Secondary structure predictions of the different families mentioned above revealed an alternating order of beta-strands and alpha-helices in agreement with a beta/alpha-barrel-like topology. The putative phosphate-binding site is always found near the C-terminus of the enzymes, which are all at least about 200 amino acids long. This is compatible with its assumed location between strand 7 and helix 8. The identification of a significant motif in functionally diverse enzymes suggests a divergent evolution of at least a considerable fraction of beta/alpha-barrels. In addition to the known accumulation of beta/alpha-barrels in the tryptophan biosynthetic pathway, we observe clusters of these enzymes in histidine biosynthesis, purine metabolism, and apparently also in thiamine biosynthesis. The substrates are mostly heterocyclic compounds.(ABSTRACT TRUNCATED AT 250 WORDS)
59.
The cytidylyltransferase superfamily: identification of the nucleotide-binding site and fold prediction.
Bork P, Holm L, Koonin EV, Sander C
Abstract + PDFThe crystal structure of glycerol-3-phosphate cytidylyltransferase from B. subtilis (TagD) is about to be solved. Here, we report a testable structure prediction based on the identification by sequence analysis of a superfamily of functionally diverse but structurally similar nucleotide-binding enzymes. We predict that TagD is a member of this family. The most conserved region in this superfamily resembles the ATP-binding HiGH motif of class I aminoacyl-tRNA synthetases. The predicted secondary structure of cytidylyltransferase and its homologues is compatible with the alpha/beta topography of the class I aminoacyl-tRNA synthetases. The hypothesis of similarity of fold is strengthened by sequence-structure alignment and 3D model building using the known structure of tyrosyl tRNA synthetase as template. The proposed 3D model of TagD is plausible both structurally, with a well packed hydrophobic core, and functionally, as the most conserved residues cluster around the putative nucleotide binding site. If correct, the model would imply a very ancient evolutionary link between class I tRNA synthetases and the novel cytidylyltransferase superfamily.
57.
Exploring the Mycoplasma capricolum genome: a minimal cell reveals its physiology.
Bork P, Ouzounis C, Casari G, Schneider R, Sander C, Dolan M, Gilbert W, Gillevet PM
1995 Jun; 16(5): 955-67. PubMed: 7476192.
Abstract + PDFWe report on the analysis of 214kb of the parasitic eubacterium Mycoplasma capricolum sequenced by genomic walking techniques. The 287 putative proteins detected to date represent about half of the estimated total number of 500 predicted for this organism. A large fraction of these (75%) can be assigned a likely function as a result of similarity searches. Several important features of the functional organization of this small genome are already apparent. Among these are (i) the expected relatively large number of enzymes involved in metabolic transport and activation, for efficient use of host cell nutrients; (ii) the presence of anabolic enzymes; (iii) the unexpected diversity of enzymes involved in DNA replication and repair; and (iv) a sizeable number of orthologues (82 so far) in Escherichia coli. This survey is beginning to provide a detailed view of how M. capricolum manages to maintain essential cellular processes with a genome much smaller than that of its bacterial relatives.
56.
Ready for a motif submission? A proposed checklist.
Bork P, Ouzounis C, McEntyre J
1995 Mar; 20(3): 104. PubMed: 7709426.
PDF55.
The SEA module: a new extracellular domain associated with O-glycosylation.
Bork P, Patthy L
1995 Jul; 4(7): 1421-5. PubMed: 7670383.
Abstract + PDFUsing a variety of homology search methods and multiple alignments, a new extracellular module was identified in (1) agrin, (2) enterokinase, (3) a 63-kDa sea urchin sperm protein, (4) perlecan, (5) the breast cancer marker MUCI (episialin), (6) the cell surface antigen 114/A10, and (7/8) two functionally uncharacterized, probably extracellular, Caenorhabditis elegans proteins. Despite the functional diversity of these adhesive proteins, a common denominator seems to be their existence in heavily glycosylated environments. In addition, the better characterized proteins mentioned above contain all O-glycosidic-linked carbohydrates such as heparan sulfate that contribute considerably to their molecular masses. The common module might regulate or assist binding to neighboring carbohydrate moieties.
54.
Challenging times for bioinformatics.
Casari G, Andrade MA, Bork P, Boyle J, Daruvar A, Ouzounis C, Schneider R, Tamames J, Valencia A, Sander C
PDF53.
Polycystic kidney disease: the complete structure of the PKD1 gene and its protein. The International Polycystic Kidney Disease Consortium.
Glücksmann-Kuis MA, Tayber O, Woolf EA, Bougueleret L, Deng NH, Alperin GD, Iris F, Lakey N, Duyk G, Schneider MC, Geng L, Zhang F, Zhao ZH, Torosian S, Zhou J, Reeders ST, Bork P, Pohlschmidt M, Löhning C, Kraus B, Nowicka U, Leung ALS, Frischauf AM
PDF52.
New protein functions in yeast chromosome VIII.
Ouzounis C, Bork P, Casari G, Sander C
1995 Nov; 4(11): 2424-8. PubMed: 8563640.
Abstract + PDFThe analysis of the 269 open reading frames of yeast chromosome VIII by computational methods has yielded 24 new significant sequence similarities to proteins of known function. The resulting predicted functions include three particularly interesting cases of translation-associated proteins: peptidyl-tRNA hydrolase, a ribosome recycling factor homologue, and a protein similar to cytochrome b translational activator CBS2. The methodological limits of the meaningful transfer of functional information between distant homologues are discussed.
51.
Characterization of the mammalian YAP (Yes-associated protein) gene and its role in defining a novel protein module, the WW domain.
Sudol M, Bork P, Einbond A, Kastury K, Druck T, Negrini M, Huebner K, Lehman D
1995 Jun 16; 270(24): 14733-41. PubMed: 7782338.
Abstract + PDFWe report cDNA cloning and characterization of the human and mouse orthologs of the chicken YAP (Yes-associated protein) gene which encodes a novel protein that binds to the SH3 (Src homology 3) domain of the Yes proto-oncogene product. Sequence comparison between mouse, human, and chicken YAP proteins showed an inserted sequence in the mouse YAP that represented an imperfect repeat of an upstream sequence. Further analysis of this sequence revealed a putative protein module that is found in various structural, regulatory, and signaling molecules in yeast, nematode, and mammals including human dystrophin. Because one of the prominent features of this sequence motif is two tryptophans (W), we named it the WW domain (Bork, P., and Sudol, M. (1994) Trends Biochem. Sci. 19, 531-533). Since its delineation, more proteins have been shown to contain this domain, and we report here on the widespread distribution of the WW module and present a discussion of its possible function. We have also shown that the human YAP gene is well conserved among higher eukaryotes, but it may not be conserved in yeast. Its expression at the RNA level in adult human tissues is nearly ubiquitous, being relatively high in placenta, prostate, ovary, and testis, but is not detectable in peripheral blood leukocytes. Using fluorescence in situ hybridization on human metaphase chromosomes and by analyzing rodent-human hybrids by Southern blot hybridization and polymerase chain reaction amplification, we mapped the human YAP gene to chromosome band 11q13, a region to which the multiple endocrine neoplasia type 1 gene has been mapped.
50.
Characterization of a novel protein-binding module--the WW domain.
Sudol M, Chen HI, Bougeret C, Einbond A, Bork P
Abstract + PDFWe have identified, characterized and cloned human, mouse and chicken cDNA of a novel protein that binds to the Src homology domain 3 (SH3) of the Yes proto-oncogene product. We subsequently named it YAP for Yes-associated protein. Analysis of the YAP sequence revealed a protein module that was found in various structural, regulatory and signaling molecules. Because one of the prominent features of this sequence motif is the presence of two conserved tryptophans (W), we named it the WW domain. Using a functional screen of a cDNA expression library, we have identified two putative ligands of the WW domain of YAP which we named WBP-1 and WBP-2. Peptide sequence comparison between the two partial clones revealed a homologous proline-rich region. Binding assays and site-specific mutagenesis have shown that the proline-rich motif binds with relatively high affinity and specificity to the WW domain of YAP, with a preliminary consensus that is different from the SH3-binding PXXP motif. This suggests that the WW domain has a role in mediating protein-protein interactions via proline-rich regions, similar but distinct from Src homology 3 (SH3) domains. Based on this finding, we hypothesize that additional protein modules exist and that they could be isolated using proline-rich peptides as functional probes.
1994 13 publication(s).
49.
Drosophila kelch motif is derived from a common enzyme fold.
Bork P, Doolittle RF
1994 Mar 11; 236(5): 1277-82. PubMed: 8126718.
Abstract + PDFA systematic screening of sequence databases with a motif hitherto found only in animal and poxvirus proteins has revealed a trail leading back to prokaryotes. Fortuitously, an X-ray structure is available for one of the identified sequences and shows the fundamental fold to be a set of circularly arranged beta sheets. This structure may be very widely distributed throughout the biological world in sialidases and some other enzymes. In bacteria, a mobile noncatalytic domain is often associated with these same enzymes.
48.
The immunoglobulin fold. Structural classification, sequence patterns and common core.
Bork P, Holm L, Sander C
1994 Sep 30; 242(4): 309-20. PubMed: 7932691.
Abstract + PDFSince the first crystal structure of an immunoglobulin revealed a modular architecture, the characteristic beta-sheet fold of the immunoglobulin domain has been found in many other proteins of diverse biological function. Here, a systematic comparison of 23 Ig domain structures with less than 25% pairwise residue identity was performed using automatic structural alignment and analysis of beta-sheet and loop topology. Sequence consensus patterns were identified for nine distinct families with at most marginal similarity to each other. The analysis reveals a common structural core of only four beta-strands (b, c, e and f), embedded in an antiparallel curled beta-sheet sandwich with a total of three to five additional strands (a, c', c'', d, g) and a characteristic intersheet angle. The variation in the position of the edge strands (a, c', c'', d and g) relative to the common core defines four different topological subtypes that correlate with the length of the intervening sequence between strands c and e, the most variable region in sequence. The switch of strand c' from one sheet to the other in seven-stranded domains appears to result from short c-e segments, rather than being a major structural discriminator. The high degree of structural flexibility outside the common core and the extreme variability of side-chain packing inside the core do not support a protein folding pathway common to all members of the structural class. Mutation rates of immunoglobulin-like domains in different proteins vary considerably. Disulfide bridges, thought to contribute to structural stability, are not necessarily invariant in number and location within a subclass.
47.
A P-loop-like motif in a widespread ATP pyrophosphatase domain: implications for the evolution of sequence motifs and enzyme activity.
Bork P, Koonin EV
Abstract + PDFA conserved amino acid sequence motif was identified in four distinct groups of enzymes that catalyze the hydrolysis of the alpha-beta phosphate bond of ATP, namely GMP synthetases, argininosuccinate synthetases, asparagine synthetases, and ATP sulfurylases. The motif is also present in Rhodobacter capsulata AdgA, Escherichia coli NtrL, and Bacillus subtilis OutB, for which no enzymatic activities are currently known. The observed pattern of amino acid residue conservation and predicted secondary structures suggest that this motif may be a modified version of the P-loop of nucleotide binding domains, and that it is likely to be involved in phosphate binding. We call it PP-motif, since it appears to be a part of a previously uncharacterized ATP pyrophophatase domain. ATP sulfurylases, NtrL, and OutB consist of this domain alone. In other proteins, the pyrophosphatase domain is associated with amidotransferase domains (type I or type II), a putative citrulline-aspartate ligase domain or a nitrilase/amidase domain. Unexpectedly, statistically significant overall sequence similarity was found between ATP sulfurylase and 3'-phosphoadenosine 5'-phosphosulfate (PAPS) reductase, another protein of the sulfate activation pathway. The PP-motif is strongly modified in PAPS reductases, but they share with ATP sulfurylases another conserved motif which might be involved in sulfate binding. We propose that PAPS reductases may have evolved from ATP sulfurylases; the evolution of the new enzymatic function appears to be accompanied by a switch of the strongest functional constraint from the PP-motif to the putative sulfate-binding motif.
46.
A new family of carbon-nitrogen hydrolases.
Bork P, Koonin EV
1994 Aug; 3(8): 1344-6. PubMed: 7987228.
Abstract + PDFUsing computer methods for database search and multiple alignment, statistically significant sequence similarities were identified between several nitrilases with distinct substrate specificity, cyanide hydratases, aliphatic amidases, beta-alanine synthase, and a few other proteins with unknown molecular function. All these proteins appear to be involved in the reduction of organic nitrogen compounds and ammonia production. Sequence conservation over the entire length, as well as the similarity in the reactions catalyzed by the known enzymes in this family, points to a common catalytic mechanism. The new family of enzymes is characterized by several conserved motifs, one of which contains an invariant cysteine that is part of the catalytic site in nitrilases. Another highly conserved motif includes an invariant glutamic acid that might also be involved in catalysis.
45.
Sequenzvergleiche in der Genomanalyse
Bork P, Ouzounis C, Casari G, Sander C, Gillevet PM
1994; : 59-60. PID: 401.
44.
The WW domain: a signalling site in dystrophin?
Bork P, Sudol M
1994 Dec; 19(12): 531-3. PubMed: 7846762.
PDF42.
A novel RNA-binding motif in omnipotent suppressors of translation termination, ribosomal proteins and a ribosome modification enzyme?
Koonin EV, Bork P, Sander C
1994 Jun 11; 22(11): 2166-7. PubMed: 7518079.
Abstract + PDFUsing computer methods for database search, multiple alignment, protein sequence motif analysis and secondary structure prediction, a putative new RNA-binding motif was identified. The novel motif is conserved in yeast omnipotent translation termination suppressor SUP1, the related DOM34 protein and its pseudogene homologue; three groups of eukaryotic and archaeal ribosomal proteins, namely L30e, L7Ae/S6e and S12e; an uncharacterized Bacillus subtilis protein related to the L7A/S6e group; and Escherichia coli ribosomal protein modification enzyme RimK. We hypothesize that a new type of RNA-binding domain may be utilized to deliver additional activities to the ribosome.
41.
Yeast chromosome III: new gene functions.
Koonin EV, Bork P, Sander C
Abstract + PDFOne year after the release of the sequence of yeast chromosome III, we have re-examined its open reading frames (ORFs) by computer methods. More than 61% of the 171 probable gene products have significant sequence similarities in the current databases; as many as 54% have already known functions or are related to functionally characterized proteins, allowing partial prediction of protein function, 11 percentage points more than reported a year ago; 19% are similar to proteins of known three-dimensional structure, allowing model building by homology. The most interesting new identifications include a sugar kinase distantly related to ribokinases, a phosphatidyl serine synthetase, a putative transcription regulator, a flavodoxin-like protein, and a zinc finger protein belonging to a distinct subfamily. Several ORFs have similarities to uncharacterized proteins, resulting in new families in search of a function'. About 54% of ORFs match sequences from other phyla, including numerous fragments in the database of expressed sequence tags (ESTs). Most significant similarities to ESTs are with proteins in conserved families widely represented in the databases. About 30% of ORFs contain one or more predicted transmembrane segments. The increase in the power of functional and structural prediction comes from improvements in sequence analysis and from richer databases and is expected to facilitate substantially the experimental effort in characterizing the function of new gene products.
40.
Eukaryotic translation elongation factor 1 gamma contains a glutathione transferase domain--study of a diverse, ancient protein superfamily using motif search and structural modeling.
Koonin EV, Mushegian AR, Tatusov RL, Altschul SF, Bryant SH, Bork P, Valencia A
1994 Nov; 3(11): 2045-54. PubMed: 7703850.
Abstract + PDFUsing computer methods for multiple alignment, sequence motif search, and tertiary structure modeling, we show that eukaryotic translation elongation factor 1 gamma (EF1 gamma) contains an N-terminal domain related to class theta glutathione S-transferases (GST). GST-like proteins related to class theta comprise a large group including, in addition to typical GSTs and EF1 gamma, stress-induced proteins from bacteria and plants, bacterial reductive dehalogenases and beta-etherases, and several uncharacterized proteins. These proteins share 2 conserved sequence motifs with GSTs of other classes (alpha, mu, and pi). Tertiary structure modeling showed that in spite of the relatively low sequence similarity, the GST-related domain of EF1 gamma is likely to form a fold very similar to that in the known structures of class alpha, mu, and pi GSTs. One of the conserved motifs is implicated in glutathione binding, whereas the other motif probably is involved in maintaining the proper conformation of the GST domain. We predict that the GST-like domain in EF1 gamma is enzymatically active and that to exhibit GST activity, EF1 gamma has to form homodimers. The GST activity may be involved in the regulation of the assembly of multisubunit complexes containing EF1 and aminoacyl-tRNA synthetases by shifting the balance between glutathione, disulfide glutathione, thiol groups of cysteines, and protein disulfide bonds. The GST domain is a widespread, conserved enzymatic module that may be covalently or noncovalently complexed with other proteins. Regulation of protein assembly and folding may be 1 of the functions of GST.
39.
Tracing the spread of fibronectin type III domains in bacterial glycohydrolases.
Little E, Bork P, Doolittle RF
1994 Dec; 39(6): 631-43. PubMed: 7528812.
Abstract + PDFThe evolutionary spread of 22 fibronectin type III (Fn3) sequences among a dozen bacterial enzymes has been traced by searching databases with the non-Fn3 parts of the enzyme sequences. Numerous homologues were found that lacked the Fn3 domains. In each case the related sequences were aligned, phylogenetic trees were constructed, and the occurrences of Fn3 units on the trees were noted. Comparison with phylogenetic trees prepared from the Fn3 segments themselves allowed inferences to be made about when the Fn3 units were shuffled into their present positions.
38.
The modular structure of NifU proteins.
Ouzounis C, Bork P, Sander C
1994 May; 19(5): 199-200. PubMed: 8048161.
PDF37.
GeneQuiz: a workbench for sequence analysis.
Scharf M, Schneider R, Casari G, Bork P, Valencia A, Ouzounis C, Sander C
1994; 2: 348-53. PubMed: 7584411.
Abstract + PDFWe present the prototype of a software system, called GeneQuiz, for large-scale biological sequence analysis. The system was designed to meet the needs that arise in computational sequence analysis and our past experience with the analysis of 171 protein sequences of yeast chromosome III. We explain the cognitive challenges associated with this particular research activity and present our model of the sequence analysis process. The prototype system consists of two parts: (i) the database update and search system (driven by perl programs and rdb, a simple relational database engine also written in perl) and (ii) the visualization and browsing system (developed under C++/ET++). The principal design requirement for the first part was the complete automation of all repetitive actions: database updates, efficient sequence similarity searches and sampling of results in a uniform fashion. The user is then presented with "hit-lists" that summarize the results from heterogeneous database searches. The expert's primary task now simply becomes the further analysis of the candidate entries, where the problem is to extract adequate information about functional characteristics of the query protein rapidly. This second task is tremendously accelerated by a simple combination of the heterogeneous output into uniform relational tables and the provision of browsing mechanisms that give access to database records, sequence entries and alignment views. Indexing of molecular sequence databases provides fast retrieval of individual entries with the use of unique identifiers as well as browsing through databases using pre-existing cross-references. The presentation here covers an overview of the architecture of the system prototype and our experiences on its applicability in sequence analysis.(ABSTRACT TRUNCATED AT 250 WORDS)
1993 17 publication(s).
36.
An adhesive domain detected in functionally diverse receptors.
Beckmann G, Bork P
1993 Feb; 18(2): 40-1. PubMed: 8387703.
PDF35.
Entschlüsselung von Proteinfunktion mit Hilfe des Computers: Erkennung und Interpretation entfernter Sequenzähnlichkeiten.
Bork P
In: Informatik aktuell - Informatik in den Biowissenschaften, (eds. Ralf Hofestädt, Fritz Krückeberg, Thomas Lengauer) pp.67-78. BID: 16.
Publisher: Springer Verlag
PDF34.
The modular architecture of a new family of growth regulators related to connective tissue growth factor.
Bork P
Abstract + PDFRecently, several groups have characterized and sequenced members of a new family of growth regulators (originally called cef10, connective tissue growth factor, fisp-12, cyr61, or, alternatively, beta IG-M1 and beta IG-M2), all of which belong to immediate-early genes expressed after induction by growth factors or certain oncogenes. Sequence analysis of this family revealed the presence of four distinct modules. Each module has homologues in other extracellular mosaic proteins such as Von Willebrand factor, slit, thrombospondins, fibrillar collagens, IGF-binding proteins and mucins. Classification and analysis of these modules suggests the location of binding regions and, by analogy to better characterized modules in other proteins, sheds some light onto the structure of this new family.
33.
Hundreds of ankyrin-like repeats in functionally diverse proteins: mobile modules that cross phyla horizontally?
Bork P
Abstract + PDFBased on pattern searches and systematic database screening, almost 650 different ankyrin-like (ANK) repeats from nearly all phyla have been identified; more than 150 of them are reported here for the first time. Their presence in functionally diverse proteins such as enzymes, toxins, and transcription factors strongly suggests domain shuffling, but their occurrence in prokaryotes and yeast excludes exon shuffling. The spreading mechanism remains unknown, but in at least three cases horizontal gene transfer appears to be involved. ANK repeats occur in at least four consecutive copies. The terminal repeats are more variable in sequence. One feature of the internal repeats is a predicted central hydrophobic alpha-helix, which is likely to interact with other repeats. The functions of the ankyrin-like repeats are compatible with a role in protein-protein interactions.
32.
Monitoring the Evolution of Protein Modules by Sequence Analysis
Bork P
In: Futura Informationen aus dem Boehringer Ingelheim Fonds4 pp.45-47. BID: 17.
ISBN: 01796372 Publisher:
PDF31.
A trefoil domain in the major rabbit zona pellucida protein.
Bork P
1993 Apr; 2(4): 669-70. PubMed: 8518738.
PDF30.
The CUB domain. A widespread module in developmentally regulated proteins.
Bork P, Beckmann G
1993 May 20; 231(2): 539-45. PubMed: 8510165.
Abstract + PDFSequence analysis has revealed the presence of 31 copies of an extracellular domain, here called CUB, in 16 functionally diverse proteins such as the dorso-ventral patterning protein tolloid, bone morphogenetic protein 1, a family of spermadhesins, complement subcomponents Cls/Clr and the neuronal recognition molecule A5. Most of them are known to be involved in developmental processes. Our analysis of this new family includes the identification of seven previously undescribed members, the characterization of conserved features and a topology prediction of this approximately 110 residue spanning domain, which suggests an antiparallel beta-barrel similar to those in immunoglobulins.
29.
Fibronectin type III modules in the receptor phosphatase CD45 and tapeworm antigens.
Bork P, Doolittle RF
1993 Jul; 2(7): 1185-7. PubMed: 8358302.
PDF28.
An expanding family of helicases within the 'DEAD/H' superfamily.
Bork P, Koonin EV
1993 Feb 11; 21(3): 751-2. PubMed: 8382805.
PDF27.
A hybrid protein kinase-RNase in an interferon-induced pathway?
Bork P, Sander C
Abstract + PDFThe sequence of RNase L has been re-examined by computer analysis. We propose a molecular architecture of RNase L, with an unusual combination, in one protein chain, of 9 ankyrin-like repeats, a functional active protein kinase and a C-terminal catalytic RNase similar to the yeast protein, IRE1. The protein kinase may be involved in a new signal transduction pathway which remains to be discovered.
26.
Convergent evolution of similar enzymatic function on different protein folds: the hexokinase, ribokinase, and galactokinase families of sugar kinases.
Bork P, Sander C, Valencia A
1993 Jan; 2(1): 31-40. PubMed: 8382990.
Abstract + PDFKinases that catalyze phosphorylation of sugars, called here sugar kinases, can be divided into at least three distinct nonhomologous families. The first is the hexokinase family, which contains many prokaryotic and eukaryotic sugar kinases with diverse specificities, including a new member, rhamnokinase from Salmonella typhimurium. The three-dimensional structure of hexokinase is known and can be used to build models of functionally important regions of other kinases in this family. The second is the ribokinase family, of unknown three-dimensional structure, and comprises pro- and eukaryotic ribokinases, bacterial fructokinases, the minor 6-phosphofructokinase 2 from Escherichia coli, 6-phosphotagatokinase, 1-phosphofructokinase, and, possibly, inosine-guanosine kinase. The third family, also of unknown three-dimensional structure, contains several bacterial and yeast galactokinases and eukaryotic mevalonate and phosphomevalonate kinases and may have a substrate binding region in common with homoserine kinases. Each of the three families of sugar kinases appears to have a distinct three-dimensional fold, since conserved sequence patterns are strikingly different for the three families. Yet each catalyzes chemically equivalent reactions on similar or identical substrates. The enzymatic function of sugar phosphorylation appears to have evolved independently on the three distinct structural frameworks, by convergent evolution. In addition, evolutionary trees reveal that (1) fructokinase specificity has evolved independently in both the hexokinase and ribokinase families and (2) glucose specificity has evolved independently in different branches of the hexokinase family. These are examples of independent Darwinian adaptation of a structure to the same substrate at different evolutionary times. The flexible combination of active sites and three-dimensional folds observed in nature can be exploited by protein engineers in designing and optimizing enzymatic function.
23.
Prokaryotic members of a new family of putative helicases with similarity to transcription activator SNF2.
Kolstø AB, Bork P, Kvaløy K, Lindback T, Grønstadt A, Kristensen T, Sander C
1993 Mar 20; 230(2): 684-8. PubMed: 8464078.
Abstract + PDFCloning and sequence analysis of a new open reading frame from Bacillus cereus reveals the relationship to a recently identified family of putative eukaryotic transcription activators similar to the yeast SNF2 gene product. As a result of comparative analysis of sequence features conserved in all members of this family, a gene from a chilo iridescent virus, as well as a putative helicase from Escherichia coli (hepA), can also be grouped into this family. The unexpected presence of prokaryotic and viral sequences in the previously purely eukaryotic SNF2 family suggests a defined subgroup of DNA helicases present in all species, with specific function in transcription activation.
22.
Molecular modelling of the Norrie disease protein predicts a cystine knot growth factor tertiary structure.
Meitinger T, Meindl A, Bork P, Rost B, Sander C, Haasemann M, Murken J
Abstract + PDFThe X-lined gene for Norrie disease, which is characterized by blindness, deafness and mental retardation has been cloned recently. This gene has been thought to code for a putative extracellular factor; its predicted amino acid sequence is homologous to the C-terminal domain of diverse extracellular proteins. Sequence pattern searches and three-dimensional modelling now suggest that the Norrie disease protein (NDP) has a tertiary structure similar to that of transforming growth factor beta (TGF beta). Our model identifies NDP as a member of an emerging family of growth factors containing a cystine knot motif, with direct implications for the physiological role of NDP. The model also sheds light on sequence related domains such as the C-terminal domain of mucins and of von Willebrand factor.
21.
Exopolyphosphate phosphatase and guanosine pentaphosphate phosphatase belong to the sugar kinase/actin/hsp 70 superfamily.
Reizer J, Reizer A, Saier MH, Bork P, Sander C
1993 Jul; 18(7): 247-8. PubMed: 8212131.
PDF20.
A fast, sensitive pattern-matching approach for protein sequences.
Rohde K, Bork P
1993 Apr; 9(2): 183-9. PubMed: 8481821.
Abstract + PDFPattern-matching algorithms are a powerful tool for finding similarities and relationships among the steadily growing amount of known protein sequences. We present a fast, sensitive pattern-matching algorithm that describes a pattern by its physico-chemical properties rather than by occurrence of amino acids, using a fast, dynamic programming algorithm. Selected examples will demonstrate applications and advantages of our approach.
1992 9 publication(s).
18.
The modular architecture of vertebrate collagens.
Bork P
Abstract + PDFCollagens are typical mosaic proteins containing a number of shuffled domains. These domains have been classified by sequence similarity in order to characterize their structural and functional relationships to other proteins. This analysis provides an overview of homologies of collagen domains. It also reveals two new relationships: (i) a module common to type V, IX, XI, and XII collagens was found to be homologous to the heparin binding domain of thrombospondin; (ii) the modular architecture of a human type VII collagen fragment was identified. Its N-terminal globular domain contains fibronectin type III repeats located adjacent to a Von Willebrand factor type A module. The proposed structural similarities point to analogous subfunctions of the respective domains in otherwise distinct proteins.
17.
Proposed acquisition of an animal protein domain by bacteria.
Bork P, Doolittle RF
1992 Oct 1; 89(19): 8990-4. PubMed: 1409594.
Abstract + PDFA systematic screen of a protein sequence data base confirms that the fibronectin type III (Fn3) domain is widely distributed among animal proteins and occurs also in several bacterial carbohydrate-splitting enzymes. The motif has yet to be identified in proteins from plants or fungi. All indications are that the bacterial sequences are much too similar to the animal type to be the result of conventional vertical descent. Rather, it is likely that the bacterial units were initially acquired from an animal source and are being spread further by horizontal transfers between distantly related bacteria.
16.
Comprehensive sequence analysis of the 182 predicted open reading frames of yeast chromosome III.
Bork P, Ouzounis C, Sander C, Scharf M, Schneider R, Sonnhammer E
1992 Dec; 1(12): 1677-90. PubMed: 1304897.
Abstract + PDFWith the completion of the first phase of the European yeast genome sequencing project, the complete DNA sequence of chromosome III of Saccharomyces cerevisiae has become available (Oliver, S. G., et al., 1992, Nature 357, 38-46). We have tested the predictive power of computer sequence analysis of the 176 probable protein products of this chromosome, after exclusion of six problem cases. When the results of database similarity searches are pooled with prior knowledge, a likely function can be assigned to 42% of the proteins, and a predicted three-dimensional structure to a third of these (14% of the total). The function of the remaining 58% remains to be determined. Of these, about one-third have one or more probable transmembrane segments. Among the most interesting proteins with predicted functions are a new member of the type X polymerase family, a transcription factor with an N-terminal DNA-binding domain related to GAL4, a "fork head" DNA-binding domain previously known only in Drosophila and in mammals, and a putative methyltransferase. Our analysis increased the number of known significant sequence similarities on chromosome III by 13, to now 67. Although the near 40% success rate of identifying unknown protein function by sequence analysis is surprisingly high, the information gap between known protein sequences and unknown function is expected to widen and become a major bottleneck of genome projects in the near future. Based on the experience gained in this test study, we suggest that the development of an automated computer workbench for protein sequence analysis must be an important item in genome projects.
14.
A large domain common to sperm receptors (Zp2 and Zp3) and TGF-beta type III receptor.
Bork P, Sander C
Abstract + PDFA new family of mosaic proteins is defined by sequence analysis. The family is characterized by a 260 residue domain common to proteins of apparently diverse function and tissue specificity: sperm receptors Zp2 and Zp3, betaglycan (also called TGF-beta type III receptor), uromodulin, as well as the major zymogen granule membrane protein (GP-2). The location of the common domain is similar with respect to putative transmembrane regions. The results lead to the hypothesis that this type of domain has a common tertiary structure and that there is a functional similarity in the recognition mechanism of the sperm receptor system and the TGF-beta receptor complex.
13.
An ATPase domain common to prokaryotic cell cycle proteins, sugar kinases, actin, and hsp70 heat shock proteins.
Bork P, Sander C, Valencia A
1992 Aug 15; 89(16): 7290-4. PubMed: 1323828.
Abstract + PDFThe functionally diverse actin, hexokinase, and hsp70 protein families have in common an ATPase domain of known three-dimensional structure. Optimal superposition of the three structures and alignment of many sequences in each of the three families has revealed a set of common conserved residues, distributed in five sequence motifs, which are involved in ATP binding and in a putative interdomain hinge. From the multiple sequence alignment in these motifs a pattern of amino acid properties required at each position is defined. The discriminatory power of the pattern is in part due to the use of several known three-dimensional structures and many sequences and in part to the "property" method of generalizing from observed amino acid frequencies to amino acid fitness at each sequence position. A sequence data base search with the pattern significantly matches sugar kinases, such as fuco-, glucono-, xylulo-, ribulo-, and glycerokinase, as well as the prokaryotic cell cycle proteins MreB, FtsA, and StbA. These are predicted to have subdomains with the same tertiary structure as the ATPase subdomains Ia and IIa of hexokinase, actin, and Hsc70, a very similar ATP binding pocket, and the capacity for interdomain hinge motion accompanying functional state changes. A common evolutionary origin for all of the proteins in this class is proposed.
12.
A module of the DnaJ heat shock proteins found in malaria parasites.
Bork P, Sander C, Valencia A, Bukau B
1992 Apr; 17(4): 129. PubMed: 1585456.
PDF11.
Cloning of a gene from Bacillus cereus with homology to the mreB gene from Escherichia coli.
Narahara A, Naterstad K, Kristensen T, Lopez R, Bork P, Kolstø AB
Abstract + PDFWe have cloned and sequenced a gene coding for a putative shape-determining protein (MreB) highly homologous to the mreB gene product of Escherichia coli. The amino acid (aa) identity was 53% and the similarity 72%. The gene is expressed early in the logarithmic phase. The aa sequence comparison showed that the protein, like the E. coli MreB, has structural similarity to actin and heat-shock protein Hsc70 encoded by a new super-gene family.
1991 5 publication(s).
10.
Shuffled domains in extracellular proteins.
Bork P
Abstract + PDFA comprehensive list of domains in extracellular mosaic proteins is presented. About 40 domains were distinguished by consensus patterns. A subsequent sequence database search recognized these domains in more than 200 extracellular proteins. The results point to a structural network, which may also represent the molecular basis for a complex coordination of various functions within the world of extracellular proteins.
9.
Complement components C1r/C1s, bone morphogenic protein 1 and Xenopus laevis developmentally regulated protein UVS.2 share common repeats.
Bork P
Abstract + PDFProperty patterns were constructed, based on an alignment of related domains in human complement subcomponents C1r and C1s as well as in the sea urchin protein uEGF. This kind of consensus pattern was able to identify similar domains in a human bone morphogenic protein, in a Xenopus laevis embryonal protein involved in dorsoanterior development and in a calcium-dependent serine protease secreted from malignant hamster embryo fibroblast cells. Because of the high level of overall sequence homology this protease may be the hamsters' equivalent of the human complement subcomponent C1s. The resulting multiple alignment of all studied domains suggests functionally and structurally important regions.
8.
On alpha-helices terminated by glycine. 2. Recognition by sequence patterns.
Bork P, Preissner R
1991 Oct 31; 180(2): 666-72. PubMed: 1953738.
Abstract + PDFConsensus sequence patterns were constructed to describe helix ends with a characteristic conformation caused by specific three-center hydrogen bonds. This special type of hydrogen bond pattern comprises about one third of all helices and mostly contains glycine with a positive torsion angle phi at the helix ends. After a simple clustering procedure 6 resulting consensus sequence patterns were able to identify 501 out of 575 helix ends in the Brookhaven Protein Data Bank, showing the above-mentioned features. The patterns did not detect any false segment, but numerous sequence segments not identified by structural criteria were recognized. It is likely that they are indeed helices terminated by glycine with a positive torsion angle phi.
7.
More von Willebrand factor type A domains? Sequence similarities with malaria thrombospondin-related anonymous protein, dihydropyridine-sensitive calcium channel and inter-alpha-trypsin inhibitor.
Bork P, Rohde K
PDF6.
On alpha-helices terminated by glycine. 1. Identification of common structural features.
Preissner R, Bork P
1991 Oct 31; 180(2): 660-5. PubMed: 1953737.
Abstract + PDFAbout one third of all helices is terminated by residues with a positive torsion angle phi. 74% of them are glycines. This strong propensity can be explained by typical bifurcated three-center hydrogen bonds which are only compatible with a positive torsion angle phi, causing helix termination. An algorithm was developed to identify these structural features in alpha-helices. 158 out of 456 helices in 79 different well-refined protein structures examined in our analysis were found to have a glycine with this special conformation which have been conserved remarkably during evolution.
1990 3 publication(s).
5.
Erkennung und Nutzung von Eigenschaftensmustern in Proteinsequenzen
Bork P
In: Dissertation A, Universität LeipzigBID: 15.
Publisher: -
4.
Recognition of different nucleotide-binding sites in primary structures using a property-pattern approach.
Bork P, Grunwald C
1990 Jul 31; 191(2): 347-58. PubMed: 2384083.
Abstract + PDFConsensus sequence patterns for beta-alpha-beta folds binding FAD, NAD and GTP were constructed on the basis of 11 steric and physicochemical properties. These property patterns permit detection and distinction of the respective nucleotide-binding sites on the basis of amino acid sequence analysis alone. The SWISS-PROT database (release 9) was screened with the three calculated patterns, and nucleotide-binding sites identified are presented. They correspond to existing structure data (if known). For the detected sequence segments we are able to predict the beta-alpha-beta motif as well as the respective binding sites. For some of the proteins so detected a nucleotide-binding capacity has not previously been reported.
3.
Sequence similarities between tryptophan synthase beta subunit and other pyridoxal-phosphate-dependent enzymes.
Bork P, Rohde K
1990 Sep 28; 171(3): 1319-25. PubMed: 2222447.
Abstract + PDFOn the basis of 8 tryptophan synthase beta subunits (EC 4.2.1.20) consensus patterns were constructed comprising two conserved motifs. Screening of the SWISSPROT protein sequence database with these patterns indicates similarities with O-acetylserine sulfhydrolases (EC 4.2.99.8), threonine synthases (EC 4.2.99.2), L- and D-serine dehydratases (EC 4.2.1.13/EC 4.2.1.14) and threonine dehydratases (EC 4.2.1.16). Using multiple alignment procedures the similar regions could be extended. In connection with their pyridoxal-phosphate-binding-capacity and their positions in biochemical pathways evolutionary relationships among these enzymes are discussed.
1989 2 publication(s).
2.
Recognition of functional regions in primary structures using a set of property patterns.
Bork P
Abstract + PDF32 consensus patterns for a set of functional regions and structural motifs in protein sequences were constructed. The pattern definition is heuristic and based on 11 selected steric and physicochemical properties. By comparison with these patterns, it was possible to identify, without false detection, 1532 sites in 8702 protein sequences of SWISSPROT. Screening against such a pattern library offers a considerable chance to identify functional regions or structural motifs in proteins from which only the sequence is known.
1.
A method for property pattern searches in protein sequence databases, demonstrated by detection of GTP binding sites.
Bork P, Grunwald C
1989; 129: 231-240. PID: 304.
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