RecA protein is required for homologous recombination mediated by both the RecBCD and RecFOR pathways in E. coli. In addition to promoting genetic recombination, RecA plays an important role in the recombinational repair of DNA damage, and the induction of the SOS system in response to DNA damage. The E. coli RecA protein has multiple biochemical functions: it binds to both single- and double-stranded DNA, it promotes pairing and exchange of homologous DNA, it catalyzes ATP hydrolysis, and it promotes the proteolytic cleavage of several proteins including LexA, UmuD, and the lambda cI repressor. The structure and function of RecA is shown on the following website

RecA is highly conserved between bacteria. Homologs of RecA have also been found in Archae (RadA and RadB), Eukarya (Rad51, Rad57, Rad55 and DMC1), and phage (e.g., the phage T4 UvsX protein). The RecA protein family website provides links to recA sequences from a variety of organisms.

The following website shows a variety of electron micrographs of RecA protein coated DNA and recombination complexes:

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Last modified October 2, 2003