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Quorum-sensing quenching by rhizobacterial volatiles
Leonid Chernin1, Natela Toklikishvili, Marianna Ovadis
1Otto Warburg Center for Agricultural Biotechnology, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel. Institute of Molecular Genetics, Russian Academy of Sciences, Moscow 123182, Russia.
Environmental Microbiology Reports
|June 14, 2013
Summary
Bacterial volatile organic compounds (VOCs) can disrupt N-acyl homoserine lactone (AHL) mediated quorum-sensing (QS) communication. This discovery suggests bacterial volatiles, like AHLs, are key signaling molecules in the rhizosphere.
Area of Science:
- Microbiology
- Plant-Microbe Interactions
- Chemical Ecology
Background:
- Quorum-sensing (QS) is a cell-cell communication system in bacteria regulated by N-acyl homoserine lactone (AHL) signal molecules.
- Rhizospheric bacteria utilize QS for various functions, influencing plant health and soil ecosystems.
- Understanding QS regulation is crucial for manipulating bacterial communities in agricultural and environmental settings.
Purpose of the Study:
- To investigate the potential of volatile organic compounds (VOCs) produced by specific rhizospheric bacteria to inhibit AHL-mediated QS.
- To identify bacterial volatiles that act as quorum-quenching agents.
- To explore the role of bacterial volatiles as signaling molecules in the rhizosphere.
Main Methods:
- Treatment of AHL-producing bacteria with VOCs from Pseudomonas fluorescens B-4117 and Serratia plymuthica IC1270.
- Analysis of AHL levels using Liquid Chromatography-Mass Spectrometry/Mass Spectrometry (LC-MS/MS).
- Quantitative Reverse Transcription Polymerase Chain Reaction (qRT-PCR) to assess the expression of AHL synthase genes.
Main Results:
- VOCs from strains B-4117 and IC1270, including dimethyl disulfide (DMDS), significantly reduced AHL concentrations in various bacterial strains.
- VOCs from Pseudomonas chlororaphis 449 suppressed its own QS activity.
- Treatment with VOCs or DMDS led to significant suppression of AHL synthase gene transcription.
Conclusions:
- Bacterial VOCs can act as quorum-quenching agents, inhibiting AHL-based QS.
- Dimethyl disulfide (DMDS) is identified as a key quorum-quenching volatile.
- Bacterial volatiles represent a novel class of signaling molecules involved in microbial communication within the rhizosphere.
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