Molecular mechanisms of bacterial quorum sensing as a new drug target.

Bacterial quorum sensing evolved as a means for bacterial communities to rapidly and coordinately change genome expression patterns in response to environmental cues. Each cell in a community produces and responds to a signaling molecule called an autoinducer that serves as an indicator of the population density. A high concentration of autoinducer is associated with a large, often confined population, which requires altered gene expression for survival. Quorum sensing is one mechanism through which a bacterial population receives input from the environment and elicits an appropriate response. Because many pathogens require quorum sensing to produce virulence factors in response to association with a human host, the signaling pathway is a target for design of small-molecule inhibitors.