Regulation of virulence genes by environmental signals in Salmonella typhimurium.

Sensing and responding to environmental signals is a crucial element of bacterial pathogenicity. For a successful progression of infection, virulence gene expression is coordinated in response to habitat-specific environmental signals from the host organism. We are interested in identifying environmental cues affecting the expression of genes within Salmonella Pathogenicity Island 2 (SPI2), a virulence locus important for systemic infections by S. typhimurium. We describe our approach starting with the identification of new virulence genes, and analysis of the regulation of these genes by environmental signals leading to the proteome analysis in order to define the SPI2 regulon.