Bonnie Bassler

"Quorum sensing, or the control of gene expression in response to cell density, is used by both Gram-negative and Gram-positive bacteria to regulate a variety of physiological functions. In all cases, quorum sensing involves the production and detection of extracellular signalling molecules called autoinducers. While universal signalling themes exist, variations in the design of the extracellular signals, the signal detection apparatuses, and the biochemical mechanisms of signal relay have allowed quorum sensing systems to be exquisitely adapted for their varied uses."

"Quorum sensing-controlled behaviors are those that only occur when bacteria are at high cell population densities. These behaviors are ones that are unproductive when undertaken by an individual bacterium but become effective by the simultaneous action of a group of cells. For example, quorum sensing regulates bioluminescence, virulence factor expression, biofilm formation, sporulation, and mating. Quorum sensing is achieved through the production, release, and subsequent detection of and response to threshold concentrations of signal molecules called autoinducers. The accumulation of a stimulatory concentration of an extracellular autoinducer can only occur when a sufficient number of cells, a “quorum,” is present."

"... if we could either keep harmful bacteria from communicating, or help beneficial bacteria to communicate, those could be new kinds of therapeutics that could be developed in the future."