Quorum sensing (QS) is a mechanism of cell-cell communication mediated by signal molecules that regulates phenotypes in response to high population density. This process involves the production and detection of chemical signaling molecules called autoinducers which act upon gene expression. Numerous microorganisms use QS in order to adapt to changes in diverse environments. In Gram-negative bacteria, the most well documented quorum-dependent regulation is mediated by autoinducers called N-acyl homoserine lactones (AHLs), also referred to as auto-inducer-1. Some well-characterized QS circuits involving AHL as signaling molecules will be reviewed for better understanding of how the wiring of regulatory components achieves different biological goals.

Toward a systematic genomic survey of bacterial QS genes: cross cutting regulatory and genomic concepts