GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.

Have any questions? Please email us at ecoliwiki@gmail.com

PMID:16803956

From GONUTS
Jump to: navigation, search
Citation

Clarke, MB, Hughes, DT, Zhu, C, Boedeker, EC and Sperandio, V (2006) The QseC sensor kinase: a bacterial adrenergic receptor. Proc. Natl. Acad. Sci. U.S.A. 103:10420-5

Abstract

Quorum sensing is a cell-to-cell signaling mechanism in which bacteria respond to hormone-like molecules called autoinducers (AIs). The AI-3 quorum-sensing system is also involved in interkingdom signaling with the eukaryotic hormones epinephrine/norepinephrine. This signaling activates transcription of virulence genes in enterohemorrhagic Escherichia coli O157:H7. However, this signaling system has never been shown to be involved in virulence in vivo, and the bacterial receptor for these signals had not been identified. Here, we show that the QseC sensor kinase is a bacterial receptor for the host epinephrine/norepinephrine and the AI-3 produced by the gastrointestinal microbial flora. We also found that an alpha-adrenergic antagonist can specifically block the QseC response to these signals. Furthermore, we demonstrated that a qseC mutant is attenuated for virulence in a rabbit animal model, underscoring the importance of this signaling system in virulence in vivo. Finally, an in silico search found that the periplasmic sensing domain of QseC is conserved among several bacterial species. Thus, QseC is a bacterial adrenergic receptor that activates virulence genes in response to interkingdom cross-signaling. We anticipate that these studies will be a starting point in understanding bacterial-host hormone signaling at the biochemical level. Given the role that this system plays in bacterial virulence, further characterization of this unique signaling mechanism may be important for developing novel classes of antimicrobials.

Links

PubMed PMC1482837 Online version:10.1073/pnas.0604343103

Keywords

Animals; Epinephrine/metabolism; Epinephrine/pharmacology; Escherichia coli/genetics; Escherichia coli/metabolism; Escherichia coli/pathogenicity; Escherichia coli Proteins/genetics; Escherichia coli Proteins/metabolism; Norepinephrine/metabolism; Norepinephrine/pharmacology; Phosphorylation; Protein Binding; Rabbits; Receptors, Adrenergic/genetics; Receptors, Adrenergic/metabolism; Signal Transduction

Significance

Annotations

Gene product Qualifier GO Term Evidence Code with/from Aspect Extension Notes Status


See also

References

See Help:References for how to manage references in GONUTS.