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Specificity and polymorphism of the PlcR-PapR quorum-sensing system in the Bacillus cereus group.

ABSTRACT: The expression of extracellular virulence factors in various species of the Bacillus cereus group is controlled by the plcR and papR genes, which encode a transcriptional regulator and a cell-cell signaling peptide, respectively. A processed form of PapR, presumably a pentapeptide, specifically interacts with PlcR to facilitate its binding to its DNA targets. This activating mechanism is strain specific, with this specificity being determined by the first residue of the pentapeptide. We carried out in vivo complementation assays and compared the PlcR-PapR sequences of 29 strains from the B. cereus group. Our findings suggested that the fifth amino acid of the pentapeptide is also involved in the specificity of activation. We identified four classes of PlcR-PapR pairs, defining four distinct pherotypes in the B. cereus group. We used these findings to look at the evolution of the PlcR-PapR quorum-sensing system with regard to the phylogeny of the species forming the B. cereus group.

SUBMITTER: Slamti L

PROVIDER: S-EPMC545710 | biostudies-literature | 2005 Feb

REPOSITORIES: biostudies-literature

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Specificity and polymorphism of the PlcR-PapR quorum-sensing system in the Bacillus cereus group.

Slamti Leyla L Lereclus Didier D

Journal of bacteriology 20050201 3

The expression of extracellular virulence factors in various species of the Bacillus cereus group is controlled by the plcR and papR genes, which encode a transcriptional regulator and a cell-cell signaling peptide, respectively. A processed form of PapR, presumably a pentapeptide, specifically interacts with PlcR to facilitate its binding to its DNA targets. This activating mechanism is strain specific, with this specificity being determined by the first residue of the pentapeptide. We carried ...[more]

PMID: 15659693

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PapR peptide maturation: role of the NprB protease in Bacillus cereus 569 PlcR/PapR global gene regulation.

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Molecular basis for group-specific activation of the virulence regulator PlcR by PapR heptapeptides.

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| S-EPMC2441798 | biostudies-literature

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