IMGT, the international ImMunoGeneTics database (http://imgt.cines.fr) is a high quality integrated information system specializing in immunoglobulins (IG), T cell receptors (TR) and major histocompatibility complex (MHC) of human and other vertebrates. IMGT provides a common access to expertly annotated data on the genome, proteome, genetics and structure of the IG and TR, based on the IMGT Scientific chart and IMGT-ONTOLOGY. The IMGT unique numbering defined for the IG and TR variable regions and domains of all jawed vertebrates has allowed a redefinition of the limits of the framework (FR-IMGT) and complementarity determining regions (CDR-IMGT), leading, for the first time, to a standardized description of mutations, allelic polymorphisms, 2D representations (Colliers de Perles) and 3D structures, whatever the antigen receptor, the chain type, or the species. The IMGT numbering has been extended to the V-like domain and is, therefore, highly valuable for comparative analysis and evolution studies of proteins belonging to the IG superfamily.

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The HPr-like protein Crh has so far been detected only in the bacillus group of bacteria. In Bacillus subtilis, its gene is part of an operon composed of six ORFs, three of which exhibit strong similarity to genes of unknown function present in many bacteria. The promoter of the operon was determined and found to be constitutively active. A deletion analysis revealed that gene yvcK, encoded by this operon, is essential for growth on Krebs cycle intermediates and on carbon sources metabolized via the pentose phosphate pathway. In addition, cells lacking YvcK acquired media-dependent filamentous or L-shape-like aberrant morphologies. The presence of high magnesium concentrations restored normal growth and cell morphology. Furthermore, suppressor mutants cured from these growth defects appeared spontaneously with a high frequency. Such suppressing mutations were identified in a transposon mutagenesis screen and found to reside in seven different loci. Two of them mapped in genes of central carbon metabolism, including zwf, which encodes glucose-6-phosphate dehydrogenase and cggR, the product of which regulates the synthesis of glyceraldehyde-3-phosphate dehydrogenase. All these results suggest that YvcK has an important role in carbon metabolism, probably in gluconeogenesis required for the synthesis of cell wall precursor molecules. Interestingly, the Escherichia coli homologous protein, YbhK, can substitute for YvcK in B. subtilis, suggesting that the two proteins have been functionally conserved in these different bacteria.