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Lipopeptide Interplay Mediates Molecular Interactions between Soil Bacilli and Pseudomonads
Sofija Andrić1, Thibault Meyer1, Augustin Rigolet1
1Microbial Processes and Interactions Laboratory, Terra Teaching and Research Centre, Gembloux Agro-Bio Tech, University of Liègegrid.4861.b, Gembloux, Belgium.
Microbiology Spectrum
|December 8, 2021
Summary
Bacillus velezensis uses lipopeptides to enhance its movement and neutralize harmful Pseudomonas lipopeptides. This interaction helps Bacillus survive and persist in the competitive plant root environment.
Area of Science:
- Microbial Ecology
- Plant-Microbe Interactions
- Biocontrol Agents
Background:
- Bacillus velezensis is a plant-associated bacterium known for biocontrol properties.
- Interactions between B. velezensis and soil competitors like Pseudomonas are crucial for ecological fitness but poorly understood.
- The role of secondary metabolites in these interactions needs further investigation.
Purpose of the Study:
- To investigate the molecular mechanisms of interaction between B. velezensis and Pseudomonas.
- To identify the role of secondary metabolites, specifically lipopeptides, in interspecies competition.
- To understand how these interactions influence bacterial fitness in the rhizosphere.
Main Methods:
- In vitro confrontation assays between B. velezensis and Pseudomonas strains.
- Analysis of macroscopic outcomes including growth inhibition and motility.
- Identification and correlation of lipopeptide production with observed phenotypes.
- Competitive root colonization assays in tomato plants.
Main Results:
- B. velezensis exhibited inhibited growth, white line formation, and enhanced motility upon contact with Pseudomonas.
- Specific lipopeptides were identified as key mediators of these interactions.
- Bacillus mobilized surfactin to increase motility and act as a chemical trap against Pseudomonas lipopeptides.
- Lipopeptide roles were validated in competitive colonization of tomato roots.
Conclusions:
- Bacillus velezensis utilizes lipopeptides for enhanced motility and detoxification of competitor lipopeptides.
- These findings reveal novel ecological functions for lipopeptides in microbial competition.
- Understanding these interactions is vital for designing effective microbial consortia for sustainable agriculture.
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