Negative regulation of Salmonella pathogenicity island 2 is required for contextual control of virulence during typhoid.

ABSTRACT: Salmonella enterica relies on a type III secretion system encoded in Salmonella pathogenicity island-2 (SPI-2) to survive and replicate within macrophages at systemic sites during typhoid. SPI-2 virulence is induced upon entry into macrophages, but the mechanisms of SPI-2 gene control in vivo remain unclear, particularly with regard to negative regulators that control the contextual activation of SPI-2. Here, we identified and characterized YdgT as a negative modulator of the SPI-2 pathogenicity island and established that this negative regulation is central to systemic pathogenesis because ydgT mutants overexpressing typhoid virulence genes were ultimately attenuated during infection. ydgT mutants displayed a biphasic virulence phenotype during in vivo competitive infections that consiste

SUBMITTER: Coombes BK 

PROVIDER: S-EPMC1297660 | biostudies-literature | 2005 Nov

REPOSITORIES: biostudies-literature