Dataset Information

Virulence Gene Regulation by L-Arabinose in Salmonella enterica.

ABSTRACT: Invasion of the intestinal epithelium is a critical step in Salmonella enterica infection and requires functions encoded in the gene cluster known as Salmonella Pathogenicity Island 1 (SPI-1). Expression of SPI-1 genes is repressed by L-arabinose, and not by other pentoses. Transport of L-arabinose is necessary to repress SPI-1; however, repression is independent of L-arabinose metabolism and of the L-arabinose-responsive regulator AraC. SPI-1 repression by L-arabinose is exerted at a single target, HilD, and the mechanism appears to be post-translational. As a consequence of SPI-1 repression, l-arabinose reduces translocation of SPI-1 effectors to epithelial cells and decreases Salmonella invasion in vitro. These observations reveal a hitherto unknown role of L-arabinose in gene expression control and raise the possibility that Salmonella may use L-arabinose as an environmental signal.

SUBMITTER: Lopez-Garrido J

PROVIDER: S-EPMC4512545 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Virulence Gene Regulation by L-Arabinose in Salmonella enterica.

López-Garrido Javier J Puerta-Fernández Elena E Cota Ignacio I Casadesús Josep J

Genetics 20150518 3

Invasion of the intestinal epithelium is a critical step in Salmonella enterica infection and requires functions encoded in the gene cluster known as Salmonella Pathogenicity Island 1 (SPI-1). Expression of SPI-1 genes is repressed by L-arabinose, and not by other pentoses. Transport of L-arabinose is necessary to repress SPI-1; however, repression is independent of L-arabinose metabolism and of the L-arabinose-responsive regulator AraC. SPI-1 repression by L-arabinose is exerted at a single tar ...[more]

PMID: 25991823

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Dataset Information

Virulence Gene Regulation by L-Arabinose in Salmonella enterica.

Publications

Virulence Gene Regulation by L-Arabinose in Salmonella enterica.

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