Cloning and expression in Escherichia coli of a recA-like gene from the acidophilic autotroph Thiobacillus ferrooxidans.

A recombinant plasmid, pRSR100, containing the functional analogue of the Escherichia coli recA gene was isolated from a genomic library of Thiobacillus ferrooxidans ATCC 33020. The plasmid complemented defects in DNA repair and homologous recombination in E. coli recA mutant strains. Antiserum raised against E. coli RecA protein reacted with the native but defective E. coli HB101 RecA protein; it did not react with protein extracts from the recA deletion mutant E. coli JK696, but it reacted with two protein bands in extracts of E. coli JK696(pRSR100). A single band with an apparent Mr equal to the higher-Mr band in E. coli JK696(pRSR100) was detected in T. ferrooxidans cell extracts with the E. coli RecA antiserum.