Bacterial gene regulation by alpha-hydroxyketone signaling.
Bacteria produce diffusible, small signaling molecules termed autoinducers to promote cell-cell communication. Recently, a novel class of signaling molecules, the alpha-hydroxyketones (AHKs), was discovered in the facultative human pathogens Legionella pneumophila and Vibrio cholerae. In this review, we summarize and compare findings on AHK signaling in these bacteria. The L. pneumophila lqs (Legionella quorum sensing) and V. cholerae cqs (cholera quorum sensing) gene clusters synthesize and detect Legionella autoinducer 1 (3-hydroxypentadecan-4-one) or cholera autoinducer-1 (3-hydroxytridecan-4-one), respectively. In addition to the autoinducer synthase and cognate sensor kinase encoded in the cqs locus, the lqs cluster also harbors a prototypic response regulator. AHK signaling regulates pathogen-host cell interactions, bacterial virulence, formation of biofilms or extracellular filaments, and expression of a genomic island. The lqs/cqs gene cluster is present in several environmental bacteria, suggesting that AHKs are widely used for cell-cell signaling.
Tiaden
André
A
Institute of Molecular Life Sciences, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland.
Spirig
Thomas
T
Hilbi
Hubert
H
D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D006801:Humans; D007659:Ketones / Q000378:metabolism*; D016952:Legionella pneumophila / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D005810:Multigene Family; D011494:Protein Kinases; D053038:Quorum Sensing; D015398:Signal Transduction; D014157:Transcription Factors; D014734:Vibrio cholerae / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
D007659:Ketones; D014157:Transcription Factors; D011494:Protein Kinases