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Microtiter Dish Biofilm Formation Assay
Published on: January 30, 2011
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Evolutionary flexibility in routes to mat formation by Pseudomonas
Anuradha Mukherjee1, Gunda Dechow-Seligmann1, Jenna Gallie1
1Department of Evolutionary Theory, Max Planck Institute for Evolutionary Biology, Plön, Germany.
Molecular Microbiology
|December 2, 2021
Summary
Bacteria form surface mats using exopolysaccharides, regulated by cyclic di-GMP. Even closely related species like Pseudomonas exhibit diverse genetic and molecular strategies for mat formation, highlighting evolutionary flexibility.
Area of Science:
- Microbiology
- Bacterial surface structures
- Evolutionary biology
Background:
- Bacteria form mats at air-liquid interfaces, involving exopolysaccharides regulated by cyclic di-GMP (c-di-GMP).
- Mat formation mechanisms are well-studied in Pseudomonas fluorescens SBW25, involving specific diguanylate cyclases (WspR, AwsR, MwsR) and cellulose production.
Purpose of the Study:
- To compare mat formation mechanisms in Pseudomonas simiae PICF7 and P. fluorescens A506 with P. fluorescens SBW25.
- To investigate the roles of diguanylate cyclases and exopolysaccharide production in mat formation across related Pseudomonas species.
Main Methods:
- Comparative analysis of mat formation in different Pseudomonas strains.
- Genetic analysis of diguanylate cyclases and their impact on exopolysaccharide production (cellulose, Pel, Psl, Pga).
- Identification of novel pathways for mat formation.
Main Results:
- P. simiae PICF7 forms mats via mutations in the same diguanylate cyclases as SBW25, but produces Pel exopolysaccharide instead of cellulose.
- PICF7 exhibits at least two additional, uncharacterized routes for mat formation.
- P. fluorescens A506 utilizes semi-heritable mechanisms leading to Psl and Pga over-production for mat formation.
Conclusions:
- Bacterial mat formation displays significant evolutionary flexibility in molecular and structural pathways, even among closely related species.
- Different Pseudomonas species utilize distinct exopolysaccharides and genetic mechanisms for adapting to similar environmental conditions.
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