One-electron reduction of carcinogen chromate by microsomes, mitochondria, and Escherichia coli: Identification of Cr(V) and .OH radical

摘要: Abstract Earlier studies have shown that a long-lived Cr(V) species is produced during the reduction of chromate (Cr(VI)) by microsomes/NADPH, mitochondria, and other cellular constituents this plays significant role in mechanism Cr(VI) toxicity. The present work indicates complex involving diol moieties NADPH as ligand. Additionally, ESR spin trapping investigations show hydroxyl (.OH) radical also generated process. Hydrogen peroxide (H 2 O ) enhances .OH generation but suppresses Cr(V)-NADPH formation. Catalase decreases Measurements under anaerobic atmosphere decreased generation, indicating process molecular oxygen reduced to H , which reacts with generate via Fenton-like mechanism.