PprM, a Cold Shock Domain-Containing Protein from , Confers Oxidative Stress Tolerance to .

is a representative microorganism that is frequently used for industrial biotechnology; thus its cellular robustness should be enhanced for the widespread application of in biotechnology. Stress response genes from the extremely radioresistant bacterium have been used to enhance the stress tolerance of . In the present study, we introduced the cold shock domain-containing protein PprM from into and observed that the tolerance to hydrogen peroxide (HO) was significantly increased in recombinant strains (Ec-PprM). The overexpression of PprM in elevated the expression of some OxyR-dependent genes, which play important roles in oxidative stress tolerance. Particularly, (manganese transporter) was activated by 9-fold in Ec-PprM, even in the absence of HO stress, which induced a more than 2-fold increase in the Mn/Fe ratio compared with wild type. The reduced production of highly reactive hydroxyl radicals (·OH) and low protein carbonylation levels (a marker of oxidative damage) in Ec-PprM indicate that the increase in the Mn/Fe ratio contributes to the protection of cells from HO stress. PprM also conferred HO tolerance to in the absence of OxyR. We confirmed that the HO tolerance of mutants reflected the activation of the - operon, whose expression is activated by HO in an OxyR-independent manner. Thus, the results of the present study showed that PprM could be exploited to improve the robustness of .