Proteomics


  HEADDr NAMANE Abdelkader / anamane@pasteur.fr
  MEMBERSLAURENT Christine / Dr ROUSSELLE Jean-Claude / Dr TAFELMEYER Petra


  Annual Report

Two-dimensional electrophoresis (2DE) currently remains the most popular separation technique for soluble proteins, and allows proteome mapping and comparison of protein expression under various conditions. Gel-free proteomics techniques based on mono- or multidimensional liquid chromatography coupled with tandem mass spectrometry (MDLC-MSMS) complement 2DE techniques. Two tandem mass spectrometers, the QSTAR XL, and since 2006, the 4800 MALDI-TOF/TOF exist in the laboratory.

MALDI-MS and MSMS experiments are mainly carried out to identify proteins resulting from 2DE gel spots with high confidence. We have also implemented the liquid chromatography (LC) coupled off-line to this instrument for LC-MALDI-MSMS experiments that enable identifications from a protein mixture.

In 2006, numerous proteomics approaches were carried out. One main focus was the comparative analysis of relative protein expression under different growth conditions or of different strains of an organism. For this aim, comparative 2DE or stable isotope labelling of peptides (iTRAQ) followed by MDLC-ESI-MSMS were applied to Mycobacterium tuberculosis (collaboration with N Winter, Mycobacterial Genetics), to Photorhabdus luminescens (collaboration with JF Charles, Genetics of Bacterial Genomes), and to Mycobacterium ulcerans (collaboration with G Reysset, Bacterial Molecular Genetics).

"Targeted proteomics” involves initial protein enrichment by various methodologies. This approach was widely used for different projects, especially for protein-protein interactions and phosphoproteome analyses. For instance, selective purifications of yeast protein complexes using the TAP (Tandem Affinity Purification) approach resulted in the identification of partners involved in active protein complexes. Moreover, quantitative results obtained with iTRAQ labelling gave valuable information for the understanding of the protein order assembly within the pre-60s maturation process (collaboration with A Jacquier, Molecular Interaction Genetics). The TAP method is also applied to protein analyses of Helicobacter pylori (collaboration with H de Reuse, Pathogenesis of Mucosal Bacteria). Combination of 2DE and mass spectrometry analyses led to the identification of proteins phosphorylated by Yak1 kinase in Candida albicans (collaboration with S Goyard, Fungal Biology and Pathogenicity).

In parallel to our scientific activity, which involves the Proteomics platform in many collaborative projects, we are also dedicated to service activities.

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Spectromètre de masse 4800 MALDI-TOF/TOF

The 4800 MALDI-TOF/TOF



  Web Site

More informations on our web site


  Publications

Publications 2006 of the unit on Pasteur's references database




Activity Reports 2006 - Institut Pasteur
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