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Updated: Jun 4, 2026
06:10
Following Cell-fate in E. coli After Infection by Phage Lambda
Published on: October 14, 2011
The adaptive plasticity of temperate phage λ
Sylvain Gandon1, Tapan Goel2, Joshua S Weitz2,3
1CEFE, CNRS, Univ Montpellier, EPHE, IRD, Montpellier, France.
Virus Evolution
|June 3, 2026
Summary
Bacteriophages use cellular multiplicity of infection (MOI) to adapt. A MOI-varying strategy is adaptive for temperate phages, like phage lambda, in environments with fluctuating host densities, promoting viral persistence.
Area of Science:
- Microbiology
- Evolutionary Biology
- Virology
Background:
- Temperate phages, such as phage lambda, exhibit two infection outcomes: lytic growth or lysogenization.
- Lysogenization probability is influenced by phage/host genetics and environmental factors, notably cellular multiplicity of infection (MOI).
- Increased MOI correlates with higher lysogenization probability, indicating phenotypic plasticity, but evolutionary drivers are unclear.
Purpose of the Study:
- To investigate the evolutionary selective forces driving plasticity in phage lambda lysogenization.
- To determine if a MOI-varying strategy is adaptive under fluctuating environmental conditions.
Main Methods:
- Mathematical modeling of phage-host interactions.
- Analysis of evolutionary game theory principles applied to viral infection strategies.
- Simulation of viral population dynamics under periodic host density fluctuations.
Main Results:
- A MOI-varying strategy for lysogenization is evolutionarily adaptive when susceptible host cell populations fluctuate periodically.
- The speed of host density fluctuations and within-host decision rules significantly impact the evolution of viral plasticity.
- MOI serves as an indirect cue for viruses to adapt to changing host availability.
Conclusions:
- Natural selection favors MOI-dependent lysogenization strategies in temperate phages.
- This plasticity allows viruses to persist in environments with dynamic host densities.
- Complex genetic regulation of lysogeny can be shaped by selection pressures related to host availability.
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