Endogenous Protein S-Nitrosylation in E. coli : Regulation by OxyR

Abstract

Handling Nitrosative Stress S-nitrosylation of proteins is a principal mechanism of cellular signaling in eukaryotes but has not been reported in microbes. The transcription factor OxyR serves to protect bacterial cells from reactive oxygen species produced by cell metabolism in the presence of oxygen. Seth et al. (p. 470) found that when cells grew in the presence of nitrate, OxyR was modified by S-nitrosylation of the same cysteine residue that gets oxidized in cells grown aerobically. However, the nitrosylated OxyR activated a different set of genes—some of which appeared to protect the cell from excessive S-nitrosylation.