YgjD and YeaZ are involved in the repair of DNA cross-links

Onodera, Takefumi; Sato, Katsuya; Ota, Toshihiro*; Narumi, Issei

Orthologs of and genes are highly conserved in various organisms. The genome of the radioresistant bacterium possesses single orthologs of (DR_0382) and (DR_0756). Complete loss of either one or both genes did not result in any significant changes in cell growth efficiency, indicating that both genes are not essential for cell viability in , unlike the case with other species such as , and . Survival rates following DNA damage induced by hydrogen peroxide, -methyl--nitro--nitrosoguanidine, ultra violet radiation, -rays, cisplatin and mitomycin C (MMC) were compared among the wild-type strain and / null mutants. Interestingly, the null mutants exhibited high sensitivity to MMC, which mainly causes interstrand DNA cross-links. The sensitivity of the null mutants to MMC was restored to that of the wild-type by transformation with plasmids expressing these genes. These results suggest that and genes are involved in DNA repair and play a role in the repair of DNA cross-links in .