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Published on: October 2, 2012
Bacterial gene regulation by alpha-hydroxyketone signaling
André Tiaden1, Thomas Spirig, Hubert Hilbi
1Institute of Molecular Life Sciences, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland.
Trends in Microbiology
|April 13, 2010
Summary
Alpha-hydroxyketones (AHKs) are novel signaling molecules used by bacteria like Legionella pneumophila and Vibrio cholerae for cell-cell communication. This bacterial quorum sensing regulates virulence, biofilm formation, and host interactions.
Area of Science:
- Microbiology
- Bacterial Communication
- Molecular Biology
Background:
- Bacteria utilize autoinducers for cell-cell communication.
- Alpha-hydroxyketones (AHKs) represent a newly identified class of bacterial signaling molecules.
- AHKs have been found in facultative human pathogens, including Legionella pneumophila and Vibrio cholerae.
Purpose of the Study:
- To review and compare findings on alpha-hydroxyketone (AHK) signaling in Legionella pneumophila and Vibrio cholerae.
- To highlight the roles of AHK signaling in bacterial physiology and pathogenesis.
- To discuss the potential widespread distribution of AHK signaling systems.
Main Methods:
- Comparative analysis of AHK synthesis and detection gene clusters (lqs and cqs).
- Review of published literature on AHK signaling pathways and regulatory mechanisms.
- Examination of the known functions regulated by AHKs in L. pneumophila and V. cholerae.
Main Results:
- The lqs (Legionella quorum sensing) and cqs (cholera quorum sensing) gene clusters encode the synthesis and detection of specific AHKs (LAI-1 and CAI-1).
- The lqs cluster contains an autoinducer synthase, sensor kinase, and a response regulator, while the cqs locus has the synthase and sensor kinase.
- AHK signaling influences pathogen-host interactions, virulence, biofilm formation, and genomic island expression.
Conclusions:
- AHK signaling is a significant mechanism for bacterial communication in L. pneumophila and V. cholerae.
- The presence of lqs/cqs gene clusters in other environmental bacteria suggests AHKs are broadly utilized for cell-cell signaling.
- Further research into AHKs can reveal new targets for antimicrobial strategies.
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