Complementation between exr and uvr A strains of Escherichia coli

Summary When Pl phages grown on strain Bs12 (HCR) were used to infect exr strains Bs2, 4 and 7, and the reverse, a significant increase in survivors of ultraviolet radiation was observed over those found in selfing experiments. No such increase in survivors was found when Pl grown on each of the exr strains was used to infect each of the other exr strains. Only 1% of the survivors of UV treatment were stably resistant to UV. These data are considered a demonstration of complementation between the malB-linked, UV sensitivity genes of Bs12 (uvrA) and Bs2, 4 and 7 (exr).This work was carried out under Public Health Service Grant CA 05687-08 from the National Cancer Institute.Recipient of a Public Health Service Career Development Award.