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Biomedical subjects

Olivier Poirot

Publications and source records attributed to Olivier Poirot.

3 recordsLinked to original sources

Tcoffee@igs: A web server for computing, evaluating and combining multiple sequence alignments.

This paper presents Tcoffee@igs, a new server provided to the community by Hewlet Packard computers and the Centre National de la Recherche Scientifique. This server is a web-based tool dedicated to the computation, the evaluation and the combination of multiple sequence alignments. It uses the latest version of the T-Coffee package. Given a set of unaligned sequences, the server returns an evaluated multiple sequence alignment and the associated phylogenetic tree. This server also makes it possible to evaluate the local reliability of an existing alignment and to combine several alternative multiple alignments into a single new one. Tcoffee@igs can be used for aligning protein, RNA or DNA sequences. Datasets of up to 100 sequences (2000 residues long) can be processed. The server and its documentation are available from: http://igs-server.cnrs-mrs.fr/Tcoffee/.

Consensus Sequence↗

Phydbac (phylogenomic display of bacterial genes): An interactive resource for the annotation of bacterial genomes.

Phydbac is a web interactive resource based on phylogenomic profiling, designed to help microbiologists to annotate bacterial proteins. Phylogenomic annotation is based on the assumption that functionally linked protein-coding genes must evolve in a coordinated manner. The detection of subsets of co-evolving genes within a given genome involves the computation of protein sequence conservation profiles across a spectrum of microbial species, followed by the identification of significant pairwise correlations between them. Many ongoing studies are devoted to the problem of computing the most biologically significant phylogenomic profiles and how best identifying clusters of 'functionally interacting' genes. Here we introduce a web tool, Phydbac, allowing the dynamic construction of phylogenomic profiles of protein sequences of interest and their interactive display. In addition, Phydbac can identify Escherichia coli proteins exhibiting the evolution pattern most similar to arbitrary query protein sequences, hence providing functional hints for open reading frames (ORFs) of hypothetical or unknown function. The phylogenomic profiles of all E.coli K-12 protein-coding genes are pre-computed, allowing queries about E.coli genes to be answered instantaneously. The profiles and phylogenomic neighborhoods are computed using an original method shown to perform better than previous ones. An extension of Phydbac, including precomputed profiles for all available bacterial genomes (including major pathogens) will soon be available. Phydbac can be accessed at: http://igs-server.cnrs-mrs.fr/phydbac/.

Bacterial Proteins↗

In Ssarch of new anti-bacterial target genes: a comparative/structural genomics approach.

We outline a joint academic/industrial (CNRS/AVENTIS) functional genomics project aiming at the discovery of new anti-bacterial gene targets. Starting from all publicly available bacterial genomes, a subset of the most evolutionary conserved protein-coding genes has been identified. We retained genes with clear homolog in E. coli and at least one gram-positive bacterium among B.subtilis, M. tuberculosis, L. lactis or S. pyogenes. This subset was further reduced to genes encoding non-membrane proteins of unknown or hypothetical functions. The 221 E. coli Open Reading Frames (ORFs) identified through this comprehensive bioinformatic analysis are now submitted to a systematic 3-D structure determination protocol including cloning, protein expression and purification, crystallisation and X-ray diffraction. Our strategy was designed to focus on promising wide-spectrum targets as well as original biochemical pathways. Bioinformatics is used throughout all phases of project, including the initial large-scale comparative genomics analyses, the purification/expression and crystallisation stages for the detection of helpful sequence-specific features (e.g. cofactor binding motifs, non-structured N- or C- term extremities, etc ), and finally for the interpretation of the structures in conjunction with multiple sequence alignments for the identification of key residues, interaction areas on molecular surfaces, and overall function predictions.

Anti-Infective Agents↗