Identification, isolation and sequencing of the recA gene of Streptomyces lividans TK24.

An internal fragment of the recA gene of Streptomyces cattleya was amplified by the polymerase chain reaction (PCR) employing degenerate oligonucleotide primers. Using this fragment as a hybridization probe, a recA homologous gene could be shown in each tested Streptomyces strain. A 4.4 kb BamHI fragment which carried the complete recA gene was isolated from Streptomyces lividans TK24. Sequence analysis suggested that the coding region of the recA gene consists of 1122 bp. The highest similarity (approximately 78%) could be detected to the recA genes of Mycobacterium tuberculosis and Mycobacterium leprae. After fusion with an E. coli promoter the S. lividans recA gene could partially complement an Escherichia coli recA mutant.