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Vibrio harveyi quorum sensing: a coincidence detector for two autoinducers controls gene expression.

ABSTRACT: In a process called quorum sensing, bacteria communicate with one another by exchanging chemical signals called autoinducers. In the bioluminescent marine bacterium Vibrio harveyi, two different auto inducers (AI-1 and AI-2) regulate light emission. Detection of and response to the V.harveyi autoinducers are accomplished through two two-component sensory relay systems: AI-1 is detected by the sensor LuxN and AI-2 by LuxPQ. Here we further define the V.harveyi quorum-sensing regulon by identifying 10 new quorum-sensing-controlled target genes. Our examination of signal processing and integration in the V.harveyi quorum-sensing circuit suggests that AI-1 and AI-2 act synergistically, and that the V.harveyi quorum-sensing circuit may function exclusively as a 'coincidence detector' that discriminates between conditions in which both autoinducers are present and all other conditions.

SUBMITTER: Mok KC

PROVIDER: S-EPMC145445 | biostudies-literature | 2003 Feb

REPOSITORIES: biostudies-literature

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Vibrio harveyi quorum sensing: a coincidence detector for two autoinducers controls gene expression.

Mok Kenny C KC Wingreen Ned S NS Bassler Bonnie L BL

The EMBO journal 20030201 4

In a process called quorum sensing, bacteria communicate with one another by exchanging chemical signals called autoinducers. In the bioluminescent marine bacterium Vibrio harveyi, two different auto inducers (AI-1 and AI-2) regulate light emission. Detection of and response to the V.harveyi autoinducers are accomplished through two two-component sensory relay systems: AI-1 is detected by the sensor LuxN and AI-2 by LuxPQ. Here we further define the V.harveyi quorum-sensing regulon by identifyin ...[more]

PMID: 12574123

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