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Persistence: mechanisms for triggering and enhancing phenotypic variability
1Racah Institute of Physics and Center for Nanoscience and Nanotechnology, Hebrew University, Edmond J. Safra Campus, Jerusalem 91904, Israel. nathalieqb@phys.huji.ac.il
Current Opinion in Genetics & Development
|November 5, 2011
Summary
Microorganisms develop persister cells, a subpopulation with reduced sensitivity, when exposed to lethal agents. Environmental factors and network motifs like threshold amplification and bistability drive this microbial persistence.
Area of Science:
- Microbiology
- Systems Biology
- Biophysics
Background:
- Microbial survival curves often show an initial rapid decline followed by a slower decrease, known as tailing.
- This phenomenon is attributed to the presence of persister cells, which exhibit reduced susceptibility to lethal agents.
- Understanding the mechanisms behind persister cell formation is crucial for controlling microbial populations.
Purpose of the Study:
- To review environmental factors that induce differentiation into persister cell phenotypes.
- To explore network motifs enabling the coexistence of persister and non-persister cells in microbial populations.
- To identify key regulatory mechanisms underlying microbial persistence.
Main Methods:
- Literature review of studies on microbial survival curves and persister cell formation.
- Analysis of environmental triggers for persister cell differentiation.
- Examination of theoretical models and network motifs governing cell population dynamics.
Main Results:
- Environmental factors play a significant role in triggering the differentiation of persister cells.
- Specific network motifs, including threshold amplification of noise and bistability driven by positive feedback, are identified as key.
- These motifs facilitate the coexistence of metabolically diverse persister and non-persister cells within a population.
Conclusions:
- Microbial persistence is a complex trait regulated by environmental cues and intracellular network dynamics.
- Threshold amplification and bistability are critical network motifs enabling persister cell formation and survival.
- Further research into these mechanisms can inform strategies for antimicrobial development and microbial control.
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