| Summary: | Quorum sensing (QS) is a communication mechanism used by bacteria to recognize cell
population density fluctuations and control gene expression, which is a critical role both in
intra- and interspecies communication and controls microbe-host interactions. QS i s t he
process in which the bacterial cells detect threshold concentration of signaling molecules in the
external environment, and then after having exceeded this allowable threshold, they respond
accordingly and modify their behavior by altering the expression of their genes. Regulation of
gene expression in response to the density of bacterial cells in a population is a key phenomenon
in the mechanism of QS and it is used by both Gram-negative and Gram-positive bacteria. In
Gram-negative bacteria LuxR protein plays a key role in QS system as a type of transcription
regulators and participates in a variety of biological behaviors with LuxI protein and signal
molecules, including those encoding virulence factors and antibiotics biosynthesis, plasmid
transfer, bioluminescence, and biofilm formation. New researches which highlight the unusual
signaling molecules, novel regulatory components and heterogeneity in the QS system of
Gram-negative bacteria are presented in this paper.
|
|---|
