Quorum sensing
OVERVIEW
Quorum sensing is the capacity of micro-organisms to detect extracellular, small-molecule signals and to alter gene expression in response to microbial population densities
- These molecules are used by bacteria to modulate gene expression within their own species, as well as competing bacteria and even eukaryotes
- Successful invasion of a host is a collective process, based on microbial information sharing and active collaboration
- Quorum sensing inhibitors have potential roles as therapeutic agents
EXAMPLES
Many bacterial pathogen contain QS genes that may help coordinate host invasion (e.g. expression of virulence genes), such as:
- Streptococcus spp
- Staphylococcus spp
- Escherichia coli
- Pseudomonas aeruginosa
- Bacteroides spp
- Yersinia spp
- Burkholderia spp
- Enterococcus spp
QUORUM SENSING SYSTEMS
- Autoinducer type 1, LuxR-I type
- Autoinducer type 2, LuxS type
- Autoinducer type 3, epinephrine/norepinephrine signaling system
- Cyclic short-peptide systems
FUNCTIONS
- biofilm production and maintenance
- regulation of the bacterial virulome (virulence genes)
- disruption of the quorum sensing systems of competing species
- inhibition of growth of competing species
- modulation of host response to bacterial invasion
- sensing host stress response
References and Links
Journal articles
- Asad S, Opal SM. Bench-to-bedside review: Quorum sensing and the role of cell-to-cell communication during invasive bacterial infection. Crit Care. 2008;12(6):236. doi: 10.1186/cc7101.PMC2646340.
Critical Care
Compendium
Chris is an Intensivist and ECMO specialist at The Alfred ICU, where he is Deputy Director (Education). He is a Clinical Adjunct Associate Professor at Monash University, the Lead for the Clinician Educator Incubator programme, and a CICM First Part Examiner.
He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives. He was one of the founders of the FOAM movement (Free Open-Access Medical education) has been recognised for his contributions to education with awards from ANZICS, ANZAHPE, and ACEM.
His one great achievement is being the father of three amazing children.
On Bluesky, he is @precordialthump.bsky.social and on the site that Elon has screwed up, he is @precordialthump.
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