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An rhs gene of Pseudomonas aeruginosa encodes a virulence protein that activates the inflammasome.

ABSTRACT: The rhs genes are a family of enigmatic composite genes, widespread among Gram-negative bacteria. In this study, we characterized rhsT, a Pseudomonas aeruginosa rhs gene that encodes a toxic protein. Expression of rhsT was induced upon contact with phagocytic cells. The RhsT protein was exposed on the bacterial surface and translocated into phagocytic cells; these cells subsequently underwent inflammasome-mediated death. Moreover, RhsT enhanced host secretion of the potent proinflammatory cytokines IL-1? and IL-18 in an inflammasome-dependent manner. In a mouse model of acute pneumonia, infection with a P. aeruginosa strain lacking rhsT was associated with less IL-18 production, fewer recruited leukocytes, reduced pulmonary bacterial load, and enhanced animal survival. Thus, rhsT encodes a virulence determinant that activates the inflammasome.

SUBMITTER: Kung VL

PROVIDER: S-EPMC3268321 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature

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An rhs gene of Pseudomonas aeruginosa encodes a virulence protein that activates the inflammasome.

Kung Vanderlene L VL Khare Sonal S Stehlik Christian C Bacon Elizabeth M EM Hughes Ami J AJ Hauser Alan R AR

Proceedings of the National Academy of Sciences of the United States of America 20120109 4

The rhs genes are a family of enigmatic composite genes, widespread among Gram-negative bacteria. In this study, we characterized rhsT, a Pseudomonas aeruginosa rhs gene that encodes a toxic protein. Expression of rhsT was induced upon contact with phagocytic cells. The RhsT protein was exposed on the bacterial surface and translocated into phagocytic cells; these cells subsequently underwent inflammasome-mediated death. Moreover, RhsT enhanced host secretion of the potent proinflammatory cytoki ...[more]

PMID: 22232685

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