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Updated: May 21, 2026
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Fluorescence Live-cell Imaging of the Complete Vegetative Cell Cycle of the Slow-growing Social Bacterium Myxococcus xanthus
Published on: June 20, 2018
Coordinated phenotype switching with large-scale chromosome flip-flop inversion observed in bacteria
Longzhu Cui1, Hui-min Neoh, Akira Iwamoto
1Department of Bacteriology, Faculty of Medicine, Juntendo University, 2-1-1 Bunkyo-Ku, Tokyo, Japan. longzhu@insti.kitasato-u.ac.jp
Summary
This study reveals bacteria can undergo large, reversible genome inversions, altering traits like antibiotic resistance. This genetic flexibility acts as a bet-hedging strategy, influencing bacterial evolution and infections.
Area of Science:
- Microbiology
- Genomics
- Evolutionary Biology
Background:
- Genome inversions are common in nature, yet their functional significance remains largely unexplored.
- Understanding the role of genomic rearrangements is crucial for deciphering evolutionary processes.
Purpose of the Study:
- To investigate the function and biological meaning of large-scale, reversible genome inversions in bacteria.
- To characterize the frequency and impact of such inversions on bacterial phenotypes and population dynamics.
Main Methods:
- Comparative genomics to identify inversion footprints.
- High-frequency observation of chromosomal inversions in a bacterial model.
- Quantitative measurements and mathematical modeling to analyze switching dynamics.
Main Results:
- A bacterium was found to generate reversible, large-scale chromosomal inversions (approx. 50% of genome) at high frequencies (up to 1/4 generations).
- These inversions modulate bacterial phenotypes, including colony morphology, antibiotic susceptibility, and hemolytic activity, by altering gene expression.
- Stochastic yet self-organized switching maintains stable small colony variant and normal colony variant populations, indicating a bet-hedging strategy.
Conclusions:
- Heritable and reversible genome inversions play a significant role in governing the bacterial life cycle.
- This genomic plasticity impacts bacterial adaptation, population structure, and the progression of infections.
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