Introduction to RecA
The RecA protein is involved in at least three distinct biological processes
in E. coli:
- Homologous recombination (and the recombinational repair of DNA damage).
- DNA damage induced mutagenesis.
- Activation of the SOS system.
The RecA protein of E. coli has many distinct biochemical activties
- DNA binding (both single and double stranded).
- Pairing and exchange of homologous DNA.
- ATP hydrolysis.
- Coproteolytic cleavage of LexA, UmuD, and the lambda repressor.
Homologs of RecA have also been found in other species.
- RecA homologs have been cloned from many bacterial species. The sequence
and function of RecA is highly conserved among bacteria.
- In eukaryotes: the Rad51, Rad57, Rad55 and DMC1 proteins
- In Archaea: RadA and RadB proteins.
- In phage T4: the UvsX protein.
In addition, since there is a crystal structure available of the E.
coli RecA protein and since there are 100s of studies of the effects
of different mutations on the multiple functions of the protein, I believe
RecA can become a model for the studies of protein-structure evolution.