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Indole acts as an extracellular cue regulating gene expression in Vibrio cholerae.

ABSTRACT: Indole has been proposed to act as an extracellular signal molecule influencing biofilm formation in a range of bacteria. For this study, the role of indole in Vibrio cholerae biofilm formation was examined. It was shown that indole activates genes involved in vibrio polysaccharide (VPS) production, which is essential for V. cholerae biofilm formation. In addition to activating these genes, it was determined using microarrays that indole influences the expression of many other genes, including those involved in motility, protozoan grazing resistance, iron utilization, and ion transport. A transposon mutagenesis screen revealed additional components of the indole-VPS regulatory circuitry. The indole signaling cascade includes the DksA protein along with known regulators of VPS production, VpsR and CdgA. A working model is presented in which global control of gene expression by indole is coordinated through sigma(54) and associated transcriptional regulators.

SUBMITTER: Mueller RS

PROVIDER: S-EPMC2681914 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature

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Indole acts as an extracellular cue regulating gene expression in Vibrio cholerae.

Mueller Ryan S RS Beyhan Sinem S Saini Simran G SG Yildiz Fitnat H FH Bartlett Douglas H DH

Journal of bacteriology 20090327 11

Indole has been proposed to act as an extracellular signal molecule influencing biofilm formation in a range of bacteria. For this study, the role of indole in Vibrio cholerae biofilm formation was examined. It was shown that indole activates genes involved in vibrio polysaccharide (VPS) production, which is essential for V. cholerae biofilm formation. In addition to activating these genes, it was determined using microarrays that indole influences the expression of many other genes, including t ...[more]

PMID: 19329638

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