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Updated: May 11, 2026
06:10
Following Cell-fate in E. coli After Infection by Phage Lambda
Published on: October 14, 2011
Nongenetic individuality in the host-phage interaction
Sivan Pearl1, Chana Gabay, Roy Kishony
1Racah Institute of Physics, Hebrew University, Jerusalem, Israel.
Plos Biology
|May 23, 2008
Summary
Bacterial persistence, a nongenetic trait, protects cells from antibiotics but not from phage lambda infection. Persistent bacteria suppress phage lytic gene expression until they resume normal growth, leading to lysis.
Area of Science:
- Microbiology
- Bacteriology
- Virology
Background:
- Isogenic bacteria display diverse phenotypes without genetic changes, known as nongenetic individuality.
- Bacterial persistence, characterized by slow growth or dormancy, confers resistance to antibiotics.
Purpose of the Study:
- To investigate the impact of bacterial persistence on the interaction between Escherichia coli and phage lambda.
- To understand how nongenetic individuality influences host-phage dynamics.
Main Methods:
- Long-term time-lapse microscopy of single infected bacteria.
- Monitoring green fluorescent protein (GFP) expression under phage lytic promoter.
- Quantitative gene expression analysis and mathematical modeling.
Main Results:
- Persistent bacteria are protected from prophage induction but susceptible to lytic infection.
- Phage lytic gene expression is suppressed in persistent Escherichia coli.
- Upon exiting persistence, bacteria support phage gene expression and subsequent lysis.
Conclusions:
- Bacterial persistence modulates phage lambda infection dynamics.
- Nongenetic individuality plays a significant role in host-phage population dynamics.
- Understanding persistence is crucial for coevolutionary studies of bacteria and phages.
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