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Legionella quorum sensing and its role in pathogen-host interactions
Nicolas Personnic1, Bianca Striednig1, Hubert Hilbi1
1Institute of Medical Microbiology, University of Zürich, Gloriastrasse 30, 8006 Zürich, Switzerland.
Current Opinion in Microbiology
|December 1, 2017
Summary
Legionella pneumophila uses a quorum sensing system (Lqs) to regulate virulence and host cell interactions. This system, involving the molecule 3-hydroxypentadecane-4-one (LAI-1), is crucial for bacterial communication and pathogenicity.
Area of Science:
- Microbiology
- Bacterial Pathogenesis
- Cell Signaling
Background:
- Legionella pneumophila causes Legionnaires' disease, a severe pneumonia.
- The Legionella quorum sensing (Lqs) system regulates virulence through the α-hydroxyketone molecule 3-hydroxypentadecane-4-one (Legionella autoinducer-1, LAI-1).
- Lqs controls L. pneumophila's transition between replicative and transmissive phases, impacting competence, motility, and virulence.
Purpose of the Study:
- To review recent advances in characterizing the Lqs system.
- To explore the role of LAI-1 in L. pneumophila-host cell interactions.
- To highlight the broader implications of α-hydroxyketone signaling in bacterial communication.
Main Methods:
- Literature review of studies on the Lqs system.
- Analysis of research on LAI-1's effects on gene regulation and host cell behavior.
- Examination of the prevalence of Lqs homologues in environmental bacteria.
Main Results:
- LAI-1 regulates L. pneumophila's virulence, natural competence, and motility.
- LAI-1 directly influences host cell migration, impacting pathogen-host interactions.
- Homologues of the Lqs system are widespread in environmental bacteria, suggesting conserved signaling roles.
Conclusions:
- The Lqs system is a key regulator of L. pneumophila virulence and host interactions.
- LAI-1 mediates both inter-bacterial and inter-kingdom communication.
- α-hydroxyketone signaling represents a significant mechanism in microbial ecology and pathogenesis.
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