InterPro as a new tool for whole genome analysis. A comparative analysis of Mycobacterium tuberculosis, Bacillus subtilis and Escherichia coli as a case study

InterPro was developed as a new integrated documentation resource for protein families, domains and functional sites to rationalize the complementary efforts of the PROSITE, PRINTS, Pfam and ProDom database projects and has applications in computational functional classification of newly determined sequences lacking biochemical characterization and in comparative genome analysis. InterPro contains over 3500 entries, with more than 1000000 hits in SWISS-PROT and TrEMBL. The database is accessible for text- and sequence-based searches at http://www.ebi.ac.uk/interpro/. InterPro was used for whole proteome analysis of the pathogenic microorganism, Mycobacterium tuberculosis, and comparison with the predicted protein coding sequences of the complete genomes of Bacillus subtilis and Escherichia coli. 64.8% of the M. tuberculosis proteins in the proteome matched InterPro entries, and these could be classified according to function. The comparison with B. subtilis and E. coli provided information on the most common protein families and domains, and the most highly represented families in each organism. InterPro thus provides a useful tool for global views of whole proteomes and their compositions.     

The InterPro Database, 2003 brings increased coverage and new features

InterPro, 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).     

The Proteome Analysis database: a tool for the in silico analysis of whole proteomes

The Proteome Analysis database (http://www.ebi.ac.uk/proteome/) has been developed by the Sequence Database Group at EBI utilizing existing resources and providing comparative analysis of the predicted protein coding sequences of the complete genomes of bacteria, archeae and eukaryotes. Three main projects are used, InterPro, CluSTr and GO Slim, to give an overview on families, domains, sites, and functions of the proteins from each of the complete genomes. Complete proteome analysis is available for a total of 89 proteome sets. A specifically designed application enables InterPro proteome comparisons for any one proteome against any other one or more of the proteomes in the database.     

Proteome Analysis Database: online application of InterPro and CluSTr for the functional classification of proteins in whole genomes

The SWISS-PROT group at EBI has developed the Proteome Analysis Database utilising existing resources and providing comparative analysis of the predicted protein coding sequences of the complete genomes of bacteria, archaea and eukaryotes (http://www.ebi.ac. uk/proteome/). The two main projects used, InterPro and CluSTr, give a new perspective on families, domains and sites and cover 31-67% (InterPro statistics) of the proteins from each of the complete genomes. CluSTr covers the three complete eukaryotic genomes and the incomplete human genome data. The Proteome Analysis Database is accompanied by a program that has been designed to carry out InterPro proteome comparisons for any one proteome against any other one or more of the proteomes in the database.     

Application of InterPro for the functional classification of the proteins of fish origin in SWISS-PROT and TrEMBL

InterPro (http://www.ebi.ac.uk/interpro/) is an integrated documentation resource for protein families, domains and sites, developed initially as a means of rationalizing the complementary efforts of the PROSITE, PRINTS, Pfam and ProDom database projects. It is a useful resource that aids the functional classification of proteins. Almost 90% of the actinopterygii protein sequences from SWISS-PROT and TrEMBL can be classified using InterPro. Over 30% of the actinopterygii protein sequences currently in SWISS-PROT and TrEMBL are of mitochondrial origin, the majority of which belong to the cytochrome b/b6 family. InterPro also gives insights into the domain composition of the classified proteins and has applications in the functional classification of newly determined sequences lacking biochemical characterization, and in comparative genome analysis. A comparison of the actinopterygii protein sequences against the sequences of other eukaryotes confirms the high representation of eukaryotic protein kinase in the organisms studied. The comparisons also show that, based on InterPro families, the trans-species evolution of MHC class I and II molecules in mammals and teleost fish can be recognized.     

InterProScan--an integration platform for the signature-recognition methods in InterPro

InterProScan is a tool that scans given protein sequences against the protein signatures of the InterPro member databases, currently--PROSITE, PRINTS, Pfam, ProDom and SMART. The number of signature databases and their associated scanning tools as well as the further refinement procedures make the problem complex. InterProScan is designed to be a scalable and extensible system with a robust internal architecture. AVAILABILITY: The Perl-based InterProScan implementation is available from the EBI ftp server (ftp://ftp.ebi.ac.uk/pub/software/unix/iprscan/) and the SRS-basedInterProScan is available upon request. We provide the public web interface (http://www.ebi.ac.uk/interpro/scan.html) as well as email submission server (interproscan@ebi.ac.uk).     

CluSTr: a database of clusters of SWISS-PROT+TrEMBL proteins

The CluSTr (Clusters of SWISS-PROT and TrEMBL proteins) database offers an automatic classification of SWISS-PROT and TrEMBL proteins into groups of related proteins. The clustering is based on analysis of all pairwise comparisons between protein sequences. Analysis has been carried out for different levels of protein similarity, yielding a hierarchical organisation of clusters. The database provides links to InterPro, which integrates information on protein families, domains and functional sites from PROSITE, PRINTS, Pfam and ProDom. Links to the InterPro graphical interface allow users to see at a glance whether proteins from the cluster share particular functional sites. CluSTr also provides cross-references to HSSP and PDB. The database is available for querying and browsing at http://www.ebi.ac.uk/clustr.     

PDBsum extras: SARS‐CoV‐2 and AlphaFold models

The PDBsum web server provides structural analyses of the entries in the Protein Data Bank (PDB). Two recent additions are described here. The first is the detailed analysis of the SARS‐CoV‐2 virus protein structures in the PDB. These include the variants of concern, which are shown both on the sequences and 3D structures of the proteins. The second addition is the inclusion of the available AlphaFold models for human proteins. The pages allow a search of the protein against existing structures in the PDB via the Sequence Annotated by Structure (SAS) server, so one can easily compare the predicted model against experimentally determined structures. The server is freely accessible to all at http://www.ebi.ac.uk/pdbsum.     

E-MSD: the European Bioinformatics Institute Macromolecular Structure Database

The E-MSD macromolecular structure relational database (http://www.ebi.ac.uk/msd) is designed to be a single access point for protein and nucleic acid structures and related information. The database is derived from Protein Data Bank (PDB) entries. Relational database technologies are used in a comprehensive cleaning procedure to ensure data uniformity across the whole archive. The search database contains an extensive set of derived properties, goodness-of-fit indicators, and links to other EBI databases including InterPro, GO, and SWISS-PROT, together with links to SCOP, CATH, PFAM and PROSITE. A generic search interface is available, coupled with a fast secondary structure domain search tool.     

PDBsum1 : A standalone program for generating PDBsum analyses

PDBsum1 is a standalone set of programs to perform the same structural analyses as provided by the PDBsum web server (https://www.ebi.ac.uk/pdbsum). The server has pages for every entry in the Protein Data Bank (PDB) and can also process user‐uploaded PDB files, returning a password‐protected set of pages that are retained for around 3 months. The standalone version described here allows for in‐house processing and indefinite retention of the results. All data files and images are pre‐generated, rather than on‐the‐fly as in the web version, so can be easily accessed. The program runs on Linux, Windows, and mac operating systems and is freely available for academic use at https://www.ebi.ac.uk/thornton-srv/software/PDBsum1.     

NEWT,a new taxonomy portal

NEWT is a new taxonomy portal to the SWISS-PROT protein sequence knowledgebase. It contains taxonomy data, which is updated daily, for the complete set of species represented in SWISS-PROT, as well as those stored at the NCBI. Users can navigate through the taxonomy tree and access corresponding SWISS-PROT protein entries. In addition, a manually curated selection of external links allows access to specific information on selected species. NEWT is available at http://www.ebi.ac.uk/newt/.     

Sequence search algorithm assessment and testing toolkit (SAT)

MOTIVATION: The Sequence Search Algorithm Assessment and Testing Toolkit (SAT) aims to be a complete package for the comparison of different protein homology search algorithms. The structural classification of proteins can provide us with a clear criterion for judgment in homology detection. There have been several assessments based on structural sequences with classifications but a good deal of similar work is now being repeated with locally developed procedures and programs. The SAT will provide developers with a complete package which will save time and produce more comparable performance assessments for search algorithms. The package is complete in the sense that it provides a non-redundant large sequence resource database, a well-characterized query database of proteins domains, all the parsers and some previous results from PSI-BLAST and a hidden markov model algorithm. RESULTS: An analysis on two different data sets was carried out using the SAT package. It compared the performance of a full protein sequence database (RSDB100) with a non-redundant representative sequence database derived from it (RSDB50). The performance measurement indicated that the full database is sub-optimal for a homology search. This result justifies the use of much smaller and faster RSDB50 than RSDB100 for the SAT. AVAILABILITY: A web site is up. The whole packa ge is accessible via www and ftp. ftp://ftp.ebi.ac.uk/pub/contrib/jong/SAT http://cyrah.ebi.ac.uk:1111/Proj/Bio/SAT http://www.mrc-lmb.cam.ac.uk/genomes/SAT In the package, some previous assessment results produced by the package can also be found for reference. CONTACT: jong@ebi.ac.uk     

The EMBL sequence version archive

SUMMARY: The EMBL Nucleotide Sequence Database, maintained at the European Bioinformatics institute, is Europe's primary nucleotide sequences database. Its entries are subject to changes, but only the most recent versions are preserved in the database. The EMBL Sequence Version Archive is a new publicly available database retaining also the earlier versions of these entries. AVAILABILITY: http://www.ebi.ac.uk/embl/sva/     

The SWISS-PROT protein knowledgebase and its supplement TrEMBL in 2003

The SWISS-PROT protein knowledgebase (http://www.expasy.org/sprot/ and http://www.ebi.ac.uk/swissprot/) connects amino acid sequences with the current knowledge in the Life Sciences. Each protein entry provides an interdisciplinary overview of relevant information by bringing together experimental results, computed features and sometimes even contradictory conclusions. Detailed expertise that goes beyond the scope of SWISS-PROT is made available via direct links to specialised databases. SWISS-PROT provides annotated entries for all species, but concentrates on the annotation of entries from human (the HPI project) and other model organisms to ensure the presence of high quality annotation for representative members of all protein families. Part of the annotation can be transferred to other family members, as is already done for microbes by the High-quality Automated and Manual Annotation of microbial Proteomes (HAMAP) project. Protein families and groups of proteins are regularly reviewed to keep up with current scientific findings. Complementarily, TrEMBL strives to comprise all protein sequences that are not yet represented in SWISS-PROT, by incorporating a perpetually increasing level of mostly automated annotation. Researchers are welcome to contribute their knowledge to the scientific community by submitting relevant findings to SWISS-PROT at swiss-prot@expasy.org.     

The predictive power of the CluSTr database

SUMMARY: The CluSTr database employs a fully automatic single-linkage hierarchical clustering method based on a similarity matrix. In order to compute the matrix, first all-against-all pair-wise comparisons between protein sequences are computed using the Smith-Waterman algorithm. The statistical significance of the similarity scores is then assessed using a Monte Carlo analysis, yielding Z-values, which are used to populate the matrix. This paper describes automated annotation experiments that quantify the predictive power and hence the biological relevance of the CluSTr data. The experiments utilized the UniProt data-mining framework to derive annotation predictions using combinations of InterPro and CluSTr. We show that this combination of data sources greatly increases the precision of predictions made by the data-mining framework, compared with the use of InterPro data alone. We conclude that the CluSTr approach to clustering proteins makes a valuable contribution to traditional protein classifications. AVAILABILITY: http://www.ebi.ac.uk/clustr/.     

UniSave: the UniProtKB sequence/annotation version database

SUMMARY: The UniProtKB Sequence/Annotation Version database (UniSave) is a comprehensive archive of UniProtKB/Swiss-Prot and UniProtKB/TrEMBL entry versions. All changed Swiss-Prot and TrEMBL entries are loaded into the UniSave as part of the public bi-weekly UniProtKB releases. Unlike the UniProtKB, which contains only the latest Swiss-Prot and TrEMBL entry versions, the UniSave provides access to previous versions of these entries. AVAILABILITY: http://www.ebi.ac.uk/uniprot/unisave     

Improvements to CluSTr: the database of SWISS-PROT+TrEMBL protein clusters

The CluSTr database (http://www.ebi.ac.uk/clustr/) offers an automatic classification of SWISS-PROT+TrEMBL proteins into groups of related proteins. The clustering is based on analysis of all pair-wise sequence comparisons between proteins using the Smith-Waterman algorithm. The analysis, carried out on different levels of protein similarity, yields a hierarchical organization of clusters. Information about domain content of the clustered proteins is provided via the InterPro resource. The introduced InterPro 'condensed graphical view' simplifies the visual analysis of represented domain architectures. Integrated applications allow users to visualize and edit multiple alignments and build sequence divergence trees. Links to the relevant structural data in Protein Data Bank (PDB) and Homology derived Secondary Structure of Proteins (HSSP) are also provided.     

GFam: a platform for automatic annotation of gene families

We have developed GFam, a platform for automatic annotation of gene/protein families. GFam provides a framework for genome initiatives and model organism resources to build domain-based families, derive meaningful functional labels and offers a seamless approach to propagate functional annotation across periodic genome updates. GFam is a hybrid approach that uses a greedy algorithm to chain component domains from InterPro annotation provided by its 12 member resources followed by a sequence-based connected component analysis of un-annotated sequence regions to derive consensus domain architecture for each sequence and subsequently generate families based on common architectures. Our integrated approach increases sequence coverage by 7.2 percentage points and residue coverage by 14.6 percentage points higher than the coverage relative to the best single-constituent database within InterPro for the proteome of Arabidopsis. The true power of GFam lies in maximizing annotation provided by the different InterPro data sources that offer resource-specific coverage for different regions of a sequence. GFam’s capability to capture higher sequence and residue coverage can be useful for genome annotation, comparative genomics and functional studies. GFam is a general-purpose software and can be used for any collection of protein sequences. The software is open source and can be obtained from http://www.paccanarolab.org/software/gfam/.     

XEMBL: distributing EMBL data in XML format

Data in the EMBL Nucleotide Sequence Database is traditionally available in a flat file format that has a number of known shortcomings. With XML rapidly emerging as a standard data exchange format that can address some problems of flat file formats by defining data structure and syntax, there is now a demand to distribute EMBL data in an XML format. XEMBL is a service tool that employs CORBA servers to access EMBL data, and distributes the data in XML format via a number of mechanisms. AVAILABILITY: Use of the XEMBL service is free of charge at http://www.ebi.ac.uk/xembl/, and can be accessed via web forms, CGI, and a SOAP-enabled service. SUPPLEMENTARY INFORMATION: Information on the EMBL Nucleotide Sequence Database is available at http://www.ebi.ac.uk/embl/. The EMBL Object Model is available at http://corba.ebi.ac.uk/models/. Information on the EMBL CORBA servers is at http://corba.ebi.ac.uk/