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Monitoring Intraspecies Competition in a Bacterial Cell Population by Cocultivation of Fluorescently Labelled Strains
Published on: January 18, 2014
Stress-induced mutagenesis in bacteria.
1Department of Biology, Indiana University, Bloomington, Indiana 47405, USA. plfoster@indiana.edu
Critical Reviews in Biochemistry and Molecular Biology
|October 6, 2007
Summary
Bacteria activate global stress responses to survive environmental changes. These responses induce a transient mutator state, increasing genetic variability for adaptive evolution.
Area of Science:
- Microbiology
- Molecular Biology
- Evolutionary Biology
Background:
- Bacteria constantly face environmental fluctuations.
- Global response systems regulate gene expression and metabolism for survival.
- Master regulators like alternative sigma factors (e.g., RpoS, RpoH) control these responses.
Purpose of the Study:
- To investigate how bacteria adapt to environmental stresses.
- To understand the role of global stress responses in genetic variability.
- To explore the significance of the transient mutator state in bacterial evolution.
Main Methods:
- Analysis of bacterial global stress response pathways.
- Identification of master regulators controlling these responses (e.g., RpoS, ppGpp, LexA, polyphosphate).
- Examination of mechanisms increasing genetic variability during stress.
Main Results:
- Environmental stresses (nutritional deprivation, DNA damage, temperature shifts, antibiotics) induce overlapping stress response pathways.
- Common features include up-regulation of error-prone DNA polymerases, down-regulation of error-correcting enzymes, and mobile genetic element activity.
- These mechanisms collectively induce a transient mutator state in bacteria under stress.
Conclusions:
- Bacteria possess sophisticated global stress response systems.
- These systems promote genetic change, leading to a transient mutator state.
- This induced genetic variability is likely crucial for bacterial adaptive evolution.
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