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Reversible non-genetic phenotypic heterogeneity in bacterial quorum sensing
Binod B Pradhan1, Subhadeep Chatterjee
1Centre for DNA Fingerprinting and Diagnostics, Nampally, Hyderabad, 500001, India.
Molecular Microbiology
|March 8, 2014
Summary
Bacteria maintain diverse subpopulations for survival. This quorum sensing (QS) strategy ensures some cells respond to signals while others don't, improving fitness in changing environments.
Area of Science:
- Microbiology
- Evolutionary Biology
- Bacterial Social Behavior
Background:
- Bacteria use quorum sensing (QS) for density-dependent coordination.
- QS is thought to synchronize cells for collective tasks, maximizing fitness.
- Phenotypic heterogeneity may offer an evolutionary advantage as a bet-hedging strategy.
Purpose of the Study:
- To investigate the existence and maintenance of QS-responsive and non-responsive subpopulations in bacteria.
- To determine if QS-activated populations maintain heterogeneity.
- To understand the evolutionary implications of QS heterogeneity.
Main Methods:
- Utilized Pseudomonas syringae and Xanthomonas campestris as model organisms.
- Analyzed QS-responsive and non-responsive cell populations.
- Examined progeny of subpopulations to assess inheritance of heterogeneity.
Main Results:
- Identified two distinct subpopulations: QS-responsive and non-responsive cells within QS-activated populations.
- Found that exogenous QS signal addition did not significantly alter subpopulation distribution.
- Observed that progeny maintained similar heterogeneous distribution patterns.
Conclusions:
- Bacteria maintain QS-responsive and non-responsive subpopulations at high cell densities.
- This heterogeneity acts as a bet-hedging strategy for fluctuating environments.
- Allows simultaneous performance of both positively and negatively QS-regulated functions to enhance fitness.
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