Quorum sensing mechanism

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. 

Microbe-microbe Disruption of Quorum Sensing Mechanisms... 

Nes, l.F. and Eijsink, V.G.H. (1999). Regulation of group 11 peptide bacteriocin synthesis by quorum-sensing mechan-sims. In Cell-Cell Signaling in Bacteria ((eds) G.M. Dunny and S.C. Winans) ASM Press, Washington, D.C., 175-192. 

His major scientific interests are bacterial virulence and various aspects of bacteriocins and toxins including quorum sensing regulation, mode of action, and mechanisms involved in immunity and receptor targeting. 

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. 

Suga H, Smith KM (2003) Molecular Mechanisms of Bacterial Quorum Sensing as a New Dmg Target. Curr Opin Chem Biol 7 586... 

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). 

Ritchie AJ, Jansson A, Stallberg J, Nilsson P, Lysaght P, Cooley MA (2005) The Pseudomonas aeruginosa quorum-sensing molecule N-3-(oxododecanoyl)-L-homoserine lactone inhibits T-cell differentiation and cytokine production by a mechanism involving an early step in T-cell activation. Infect Immun 73 1648... 

Further, compartmentalization allows cells to control the import of nutrients and the export of products that manipulate the environment, or excrete waste. These include siderophores that enhance uptake of metal ions, quorum-sensing molecules that inform cells of the presence of others of their kind, molecules that form biofilms that allow attachment to surfaces and protection from mechanical and chemical stress, and toxins that inhibit the growth of competitors. 

In this article, we will concentrate on cell-to-cell communication in the form of quorum sensing in two unicellular groups, bacteria and yeast. Additionally, we will consider intercellular signaling in one species that is at the boundary between uni-ceUularity and multicellularity, Dictyostelium discoideum. To illustrate the diverse mechanisms of cell-to-cell communication, we will discuss their biologic function, on the one hand, and the molecular details of pheromone synthesis, signal transduction, and transcription regulation in each of these groups, on the other hand. 

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