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Updated: Oct 12, 2025
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Monitoring Intraspecies Competition in a Bacterial Cell Population by Cocultivation of Fluorescently Labelled Strains
Published on: January 18, 2014
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Non-genetic variability in microbial populations: survival strategy or nuisance?
Ethan Levien1,2, Jiseon Min3, Jane Kondev4
1John A Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, United States of America.
Reports on Progress in Physics. Physical Society (Great Britain)
|November 26, 2021
Summary
Non-genetic variability in cell populations significantly impacts population dynamics, influencing survival in uncertain environments and even in constant conditions. This review explores how cell-to-cell differences affect population behavior and evolution.
Area of Science:
- Microbiology
- Evolutionary Biology
- Systems Biology
Background:
- Phenotypic variability is common in genetically identical (isogenic) populations.
- Non-genetic variability influences population dynamics in various contexts, including antibiotic treatments and growth dynamics.
Purpose of the Study:
- To review research on the relationship between cell-to-cell variability and population dynamics.
- To discuss models explaining how phenotypic variability impacts population survival and evolution.
Main Methods:
- Literature review of experimental observations and theoretical models.
- Analysis of bet-hedging and phenotypic switching models.
- Examination of fine-grained models considering single-cell growth rates, generation times, and cell sizes.
Main Results:
- Phenotypic switching at the single-cell level can enhance population survival in uncertain environments.
- Variability in single-cell traits significantly affects population dynamics, even in stable environments.
- Model outcomes are sensitive to underlying assumptions regarding phenotypic variability.
Conclusions:
- Non-genetic variability plays a crucial role in population dynamics and survival strategies.
- Further research is needed to understand the interplay between environmental and intrinsic variability.
- The role of non-genetic variability in evolutionary dynamics requires further investigation.
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