Quorum sensing

In biology, quorum sensing or quorum signaling (QS)[1] is the process of cell-to-cell communication[2] that allows bacteria to detect and respond to cell population density by gene regulation, typically as a means of acclimating to environmental disadvantages.[3]

More specifically, quorum sensing is a type of cellular signaling, and more specifically can be considered a type of paracrine signaling. However, it also contains traits of autocrine signaling: a cell produces both an autoinducer molecule and the receptor for the autoinducer.[3] As one example, QS enables bacteria to restrict the expression of specific genes to the high cell densities at which the resulting phenotypes will be most beneficial, especially for phenotypes that would be ineffective at low cell densities and therefore too energetically costly to express.[4] Many species of bacteria use quorum sensing to coordinate gene expression according to the density of their local population. In a similar fashion, some social insects use quorum sensing to determine where to nest. Quorum sensing in pathogenic bacteria activates host immune signaling and prolongs host survival, by limiting the bacterial intake of nutrients, such as tryptophan, which further is converted to serotonin.[5] As such, quorum sensing allows a commensal interaction between host and pathogenic bacteria.[5] Quorum sensing may also be useful for cancer cell communications.[6]

In addition to its function in biological systems, quorum sensing has several useful applications for computing and robotics. In general, quorum sensing can function as a decision-making process in any decentralized system in which the components have: (a) a means of assessing the number of other components they interact with and (b) a standard response once a threshold to achieve number of components is useful for amino acid regulation is detected.

  1. ^ Cite error: The named reference Lupp-et-al-2003 was invoked but never defined (see the help page).
  2. ^ Rutherford, S. T.; Bassler, B. L. (2012). "Bacterial Quorum Sensing: Its Role in Virulence and Possibilities for Its Control". Cold Spring Harbor Perspectives in Medicine. 2 (11): a012427. doi:10.1101/cshperspect.a012427. PMC 3543102. PMID 23125205.
  3. ^ a b Postat, J; Bousso, P (September 11, 2019). "Quorum Sensing by Monocyte-Derived Populations". Frontiers in Immunology. 10 (2140): 2140. doi:10.3389/fimmu.2019.02140. PMC 6749007. PMID 31572366.
  4. ^ Papenfort, K; Bassler, B (February 11, 2017). "Quorum-Sensing Signal-Response Systems in Gram-Negative Bacteria". Nature Reviews Microbiology. 14 (9): 576–588. doi:10.1038/nrmicro.2016.89. PMC 5056591. PMID 27510864.
  5. ^ a b Jugder BE, Batista JH, Gibson JA, Cunningham PM, Asara JM, Watnick PI (September 2022). "Vibrio cholerae high cell density quorum sensing activates the host intestinal innate immune response". Cell Reports. 40 (12): 111368. doi:10.1016/j.celrep.2022.111368. PMC 9534793. PMID 36130487.
  6. ^ Ali I, Alfarouk KO, Reshkin SJ, Ibrahim ME (16 January 2018). "Doxycycline as Potential Anti-cancer Agent". Anti-Cancer Agents in Medicinal Chemistry. 17 (12): 1617–1623. doi:10.2174/1871520617666170213111951. PMID 28270076.