The InterPro database, an integrated documentation resource for protein families, domains and functional sites.

Signature databases are vital tools for identifying distant relationships in novel sequences and hence for inferring protein function. InterPro is an integrated documentation resource for protein families, domains and functional sites, which amalgamates the efforts of the PROSITE, PRINTS, Pfam and ProDom database projects. Each InterPro entry includes a functional description, annotation, literature references and links back to the relevant member database(s). Release 2.0 of InterPro (October 2000) contains over 3000 entries, representing families, domains, repeats and sites of post-translational modification encoded by a total of 6804 different regular expressions, profiles, fingerprints and Hidden Markov Models. Each InterPro entry lists all the matches against SWISS-PROT and TrEMBL (more than 1,000,000 hits from 462,500 proteins in SWISS-PROT and TrEMBL). The database is accessible for text- and sequence-based searches at http://www.ebi.ac.uk/interpro/. Questions can be emailed to interhelp@ebi.ac.uk.

InterPro--an integrated documentation resource for protein families, domains and functional sites.

MOTIVATION: InterPro is a new integrated documentation resource for protein families, domains and functional sites, developed initially as a means of rationalising the complementary efforts of the PROSITE, PRINTS, Pfam and ProDom database projects. RESULTS: Merged annotations from PRINTS, PROSITE and Pfam form the InterPro core. Each combined InterPro entry includes functional descriptions and literature references, and links are made back to the relevant parent database(s), allowing users to see at a glance whether a particular family or domain has associated patterns, profiles, fingerprints, etc. Merged and individual entries (i.e. those that have no counterpart in the companion resources) are assigned unique accession numbers. Release 1.2 of InterPro (June 2000) contains over 3000 entries, representing families, domains, repeats and sites of post-translational modification (PTMs) encoded by 6581 different regular expressions, profiles, fingerprints and Hidden Markov Models (HMMs). Each InterPro entry lists all the matches against SWISS-PROT and TrEMBL (more than 1000000 hits from 264333 different proteins out of 384572 in SWISS-PROT and TrEMBL).

ProDom and ProDom-CG: tools for protein domain analysis and whole genome comparisons.

ProDom contains all protein domain families automatically generated from the SWISS-PROT and TrEMBL sequence databases (http://www. toulouse.inra.fr/prodom.html ). ProDom-CG results from a similar domain analysis as applied to completed genomes (http://www.toulouse. inra.fr/prodomCG.html ). Recent improvements to the ProDom database and its server include: scaling up to include sequences from TrEMBL, addition of Pfam-A entries to the set of expert validated families, assignment of stable accession numbers, consistency indicators for domain families, domain arrangements of sub-families and links to Pfam-A.

Whole genome protein domain analysis using a new method for domain clustering.

We present the outcome of a systematic analysis of protein domain shuffling in 17 completed microbial genomes. This analysis has been performed using MKDOM Version 2, a completely new version of the domain clustering program MKDOM based on PSI-BLAST recursive homology searches. It allows to delineate the most frequent protein domain building blocks, which domains are found specifically in Bacteria, Archaea or yeast, and which domains are shared between two or all three domains of life. The latter are good candidates as the basic protein building blocks underlying all forms of cellular life. Statistics of multi-domain proteins indicate that some organisms such as Bacillus subtilis or Mycobacterium tuberculosis contain an abnormally high number of large multi-domain proteins. We also provide examples of highly shuffled or circularly permutated domains. A WWW graphical interface has been made available to interactively browse domain arrangements of proteins in all 17 genomes, at http:@www.toulouse.inra.fr/prodomCG.html.

Recent improvements of the ProDom database of protein domain families.

The ProDom database contains protein domain families generated from the SWISS-PROT database by automated sequence comparisons. The current version was built with a new improved procedure based on recursive PSI-BLAST homology searches. ProDom can be searched on the World Wide Web to study domain arrangements within either known families or new proteins, with the help of a user-friendly graphical interface (http://www.toulouse.inra.fr/prodom.html). Recent improvements to the ProDom server include: ProDom queries under the SRS Sequence Retrieval System; links to the PredictProtein server; phylogenetic trees and condensed multiple alignments for a better representation of large domain families, with zooming in and out capabilities. In addition, a similar server was set up to display the outcome of whole genome domain analysis as applied to 17 completed microbial genomes (http://www.toulouse.inra.fr/prodomCG.html ).

Browsing protein families via the 'Rich Family Description' format.

MOTIVATION: Multiple alignments of protein sequences are the basis of structural and functional analysis of protein families. It is however difficult even for an expert biologist to comprehend an alignment of more than 50 to 100 homologous sequences. RESULTS: This paper presents a browser for the analysis of multiple alignments of large numbers of protein sequences. Phylogenetic trees and consensus sequences are computed and used to summarise the alignments; these data are stored in a structure called Rich Family Description. Summary alignments and trees are displayed in HTML pages and can be developed or reduced by the user. This browser is used to display the ProDom domain families on the Web. Its zooming facilities allow extracting information from alignments of more than 1000 homologous sequences.

The ProDom database of protein domain families.

The ProDom database contains protein domain families generated from the SWISS-PROT database by automated sequence comparisons. It can be searched on the World Wide Web (http://protein.toulouse.inra. fr/prodom.html ) or by E-mail (prodom@toulouse.inra.fr) to study domain arrangements within known families or new proteins. Strong emphasis has been put on the graphical user interface which allows for interactive analysis of protein homology relationships. Recent improvements to the server include: ProDom search by keyword; links to PROSITE and PDB entries; more sensitive ProDom similarity search with BLAST or WU-BLAST; alignments of query sequences with homologous ProDom domain families; and links to the SWISS-MODEL server (http: //www.expasy.ch/swissmod/SWISS-MODEL.html ) for homology based 3-D domain modelling where possible.

XDOM, a graphical tool to analyse domain arrangements in any set of protein sequences.

MOTIVATION: To extract the maximum possible information from a set of protein sequences, its modular organization must be known and clearly displayed. This is important both for structural and functional analysis. RESULTS: This paper presents an algorithm and a graphical interface called XDOM which performs a systematic analysis of the modular organization of any set of protein sequences. The algorithm is an automatic method to identify putative domains from sequence comparisons. The graphical tool displays the proteins as a set of linked boxes, corresponding to its domains. The method has been tested on a family of bacterial proteins and on whole genomes. It is currently applied to the complete SWISS-PROT database to build the PRODOM database. AVAILABILITY: XDOM is available free of charge by anonymous ftp:¿¿ftp://ftp.toulouse.inra.fr/pub/xdom¿ ¿. The ProDom database can be consulted at ¿¿http://protein.toulouse.inra.fr/prodom.html¿¿.

RNAlign program: alignment of RNA sequences using both primary and secondary structures.

We have developed an algorithm and a computer program for aligning new RNA sequences with a bank of aligned homologous RNA sequences. Given a common folding structure for the bank, the program performs an alignment between the bank and a new sequence, optimal both in terms of primary and secondary structure. This method is useful to align sequences that present a common folding structure despite extensive divergence of their primary structures. It allows these preserved regions to be precisely distinguished from domains with more variable secondary structure. An optimal alignment of a sequence of length N with a bank of homologous sequences of length M is produced in O (M2N3) time and O(M2N2) space. For sequences that are too long for an algorithm of this complexity, a proposed strategy is to use a classical alignment (using only primary structure data) then improve it with the new algorithm in the regions where the bank stems are not aligned with possible stems in the new sequence. The algorithm has been implemented in Turbo Pascal on a PC, and has been used to align RNA sequences of eubacterial large ribosomal subunit.

Minimum antibiotic levels for selecting a resistance plasmid in a gnotobiotic animal model.

The minimum antibiotic concentrations for selecting an R plasmid in vivo were determined in germfree mice colonized by two isogenic strains of Escherichia coli, one of which carried an R plasmid. Seventy groups of three gnotobiotic mice were given low doses of ampicillin, colistin, flumequin, gentamicin, tetracycline, or streptomycin via drinking water for 2 weeks. The equilibrium between susceptible and resistant populations of bacteria was monitored daily in feces and compared with that of control mice given pure water. This model yielded reproducible data, and dose and response were strongly correlated. The minimum selecting doses ranged from 0.9 to 12.8 micrograms/ml of water, depending on the antibiotic and the R plasmid. The use of mathematical models and complementary in vitro experiments accounted for the effect of the low antibiotic levels.

Multiple sequence alignment with hierarchical clustering.

An algorithm is presented for the multiple alignment of sequences, either proteins or nucleic acids, that is both accurate and easy to use on microcomputers. The approach is based on the conventional dynamic-programming method of pairwise alignment. Initially, a hierarchical clustering of the sequences is performed using the matrix of the pairwise alignment scores. The closest sequences are aligned creating groups of aligned sequences. Then close groups are aligned until all sequences are aligned in one group. The pairwise alignments included in the multiple alignment form a new matrix that is used to produce a hierarchical clustering. If it is different from the first one, iteration of the process can be performed. The method is illustrated by an example: a global alignment of 39 sequences of cytochrome c.

Statistical decision rules concerning synteny or independence between markers.

Data on the segregation of human markers in somatic hybrids between permanent rodent cell lines and primary human cells were gathered and statistically analyzed, using various criteria of association. The analysis provides evidence that human chromosomes do not segregate independently in somatic cell hybrids. A statistical decision rule concerning synteny or independence between markers is proposed, and its utility in developing the gene maps of other species by means of somatic cell hybridization is explored.