pubmed:abstractText |
Bacterial cell-to-cell communication facilitates coordinated expression of specific genes in a growth rate-II and cell density-dependent manner, a process known as quorum sensing. While the discovery of a diffusible Escherichia coli signaling pheromone, termed autoinducer 2 (AI-2), has been made along with several quorum sensing genes, the overall number and coordination of genes controlled by quorum sensing through the AI-2 signal has not been studied systematically. We investigated global changes in mRNA abundance elicited by the AI-2 signaling molecule through the use of a luxS mutant that was unable to synthesize AI-2. Remarkably, 242 genes, comprising ca. 5.6% of the E. coli genome, exhibited significant transcriptional changes (either induction or repression) in response to a 300-fold AI-2 signaling differential, with many of the identified genes displaying high induction levels (more than fivefold). Significant induction of ygeV, a putative sigma(54)-dependent transcriptional activator, and yhbH, a sigma(54) modulating protein, suggests sigma(54) may be involved in E. coli quorum sensing.
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pubmed:affiliation |
Center for Agricultural Biotechnology, University of Maryland Biotechnology Institute, University of Maryland, College Park, Maryland 20742, USA.
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