biostudies-literatureUnknown83Wang TThe results of protein thiols reacting with oxidants may be different in the presence or absence of glutathione (GSH). Upon exposure to oxidants, such as Cu²⁺ and polysulfide, the multiple drug resistant regulator MarR dimer in Escherichia coli is believed to form tetramers linked by disulfide bonds between its Cys⁸⁰ thiols. We confirmed this observation in the absence of GSH; however, the MarR-Cys⁸⁰ thiol was primarily glutathionylated in the presence of GSH after MarR was treated with various oxidants, including octasulfur (S₈), Cu²⁺, H₂O₂, ClO^-, and a NO donor. When using S₈ as the oxidizing agent, we identified four pathways to induce MarR-Cys⁸⁰ glutathionylation. Since E. coliRedox biology103629https://www.ebi.ac.uk/biostudies/studies/S-EPMC12017873biostudies-literatureOxidants induce Escherichia coli MarR glutathionylation in the presence of glutathione.PMC12017873Liu HXia YXun LWang TfalseOxidants induce Escherichia coli MarR glutathionylation in the presence of glutathione.The results of protein thiols reacting with oxidants may be different in the presence or absence of glutathione (GSH). Upon exposure to oxidants, such as Cu²⁺ and polysulfide, the multiple drug resistant regulator MarR dimer in Escherichia coli is believed to form tetramers linked by disulfide bonds between its Cys⁸⁰ thiols. We confirmed this observation in the absence of GSH; however, the MarR-Cys⁸⁰ thiol was primarily glutathionylated in the presence of GSH after MarR was treated with various oxidants, including octasulfur (S₈), Cu²⁺, H₂O₂, ClO^-, and a NO donor. When using S₈ as the oxidizing agent, we identified four pathways to induce MarR-Cys⁸⁰ glutathionylation. Since E. coli2025-01-01T00:00:00Z2025 Apr2025-07-10T03:08:58.213Z2025-07-10T03:08:58.213ZS-EPMC120178734022833610.1016/j.redox.2025.103629