Quorum sensing bacteria

Sifri, C.D. (2008). Healthcare epidemiology quorum sensing bacteria talk sense. Clin Infect Dis 47, 1070-1076. 

The autoinducer is a low molecular weight compound that is easily leached from the cells into the culture medium. By the propagation of bacterial cells, the concentration of the autoinducer in the medium increases. When the concentration reaches a certain threshold, the biosynthesis of bioluminescence system begins, and the bacteria become luminescent. The process is also called quorum sensing (Fuqua et al., 1994). 

Fuqua, W. C.,Winans, S. C.,and Greenberg, E. P. (1994). Quorum sensing in bacteria the LuxR-LuxI family of cell density-responsive transcriptional regulators./. Bacteriol. 176 269-275. 

Daniels R, Vanderleyden J, Michiels J (2004) Quorum sensing and swarming migration in bacteria. FEMS Microbiol Rev 28 261-289... 

I. F. Nes V. G. H. Eijsink, Regulation of Group II Peptide Bacteriocin Synthesis by Quorum-Sensing Mechanisms. In Cell-Cell Signaling In Bacteria] G. M. Dunny, S. C. Winans, Eds. ASM Press Washington, DC, 1999 pp 175-192. 

Let s begin with the most common and simplest case communication among members of the same bacterial genus and species. In this case, quorum sensing essentially involves counting the number of like bacteria in the population. 

If we think about it for a bit, quorum sensing as a mechanism regulating the production of virulence factors makes good sense for the bacterial population. If the bacterial population is too low, secretion of virulence factors would seem to be of little use too few bacteria secreting too few virulence factor molecules to serve whatever purpose these serve for the bacteria. It would seem better to wait until the bacterial forces have massed, then release the virulence factors and have some real impact. 

Chemical communication among bacteria underlies the phenomenon of quorum sensing. 

Quorum sensing the ability of bacteria to coordinate their behavior through response to signaling molecules. 

It is believed that population density of a consortium component species mediates population function through self-awareness mechanisms such as quorum sensing , that enable bacteria to communicate among and between species in a consortium (Miller and Bassler, 2001). 

Holden, M.T.G, Chhabra, S.R. de Nys, R., Stead, P., Bainton, NJ., Hill, P.J., Manefield, M., Kumar, N Labatte, M., England, D., Rice, S., Givskov, M., Salmond, GP.C., Stewart, G.S.A.B., Bycroft, B.W., Williams, P. Quorum sensing cross-talk isolation and chemical characterization of cyclic dipeptides from Pseudomonas aeruginosa and other gram-negative bacteria. Mol Microbiol 1999 33 1254-1266. 

---