The transcriptional regulator SoxS is required for resistance of Salmonella typhimurium to paraquat but not for virulence in mice

Abstract

In Escherichia coli, the SoxRS regulon is required for resistance to redox-cycling agents which elevate cytosolic superoxide levels, as well as for resistance to nitric oxide-dependent macrophage killing. In Salmonella typhimurium, SoxS is also required for enhanced expression of Mn-superoxide dismutase and resistance to paraquat, but not for resistance to nitric oxide donor compounds in vitro, resistance to macrophage killing, or virulence in mice. Differences in other antioxidant defense systems or compensation by homologous regulons may account for species-specific differences in the role of SoxS.