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Updated: Jul 25, 2026
12:02
Molecular Evolution of the Tre Recombinase
Published on: May 29, 2008
Therefore, what are recombination proteins there for?
J Courcelle1, A K Ganesan, P C Hanawalt
1Department of Biological Sciences; Mississippi State University, 39762, USA. jcourcelle@biology.msstate.edu
Summary
The recA gene in E. coli is crucial for survival after DNA damage. Contrary to past beliefs, recA may primarily ensure DNA replication proceeds smoothly rather than promoting recombination for repair.
Area of Science:
- Molecular Biology
- Genetics
- Microbiology
Background:
- The recA gene in E. coli is vital for cell survival when DNA is damaged.
- recA was initially identified for its role in creating recombinant DNA molecules during bacterial conjugation.
Purpose of the Study:
- To re-evaluate the function of the recA gene in light of new research.
- To challenge the long-held assumption that recA's primary role in DNA repair is through recombination.
Main Methods:
- Review of classical experiments on DNA repair by recombination.
- Analysis of the known functions of recA-interacting processes like excision repair and translesion synthesis.
Main Results:
- Excision repair and translesion synthesis ensure processive DNA replication without strand exchange.
- The prevailing view that recA mainly promotes recombination during DNA repair may be inaccurate.
Conclusions:
- Recombination might not be the most effective mechanism for rescuing cells with DNA damage.
- recA's essential role could be maintaining processive replication, independent of promoting recombination.
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