title: Cytochrome P-450 catalyzed redox cycling of orthophenylphenol.
abstract: o-Phenylphenol was converted to 2,5-dihydroxy biphenyl (phenylhydroquinone) by microsomal P-450. Depending on the cofactor used, microsomal enzymes catalyzed oxidation and/or reduction of phenylhydroquinone. Phenylhydroquinone was oxidized to phenyl 2,5'-p-quinone by cumene hydroperoxide-supported microsomal P-450. Phenyl 2,5'-p-quinone was reduced to phenylhydroquinone by cytochrome P-450 reductase. This study provides direct evidence of cytochrome P-450 catalyzed redox cycling of o-phenylphenol. It is postulated that redox cycling of o-phenylphenol may play a role in o-phenylphenol-caused bladder cancer.
authors.affiliation: Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston 77550.
authors.forename: D
authors.initials: D
authors.lastname: Roy
mesh_terms: D000818:Animals; D001713:Biphenyl Compounds / Q000378:metabolism* / Q000633:toxicity; D002273:Carcinogens; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D006873:Hydroquinones / Q000378:metabolism; D066298:In Vitro Techniques; D008861:Microsomes / Q000201:enzymology; D010084:Oxidation-Reduction; D001749:Urinary Bladder Neoplasms / Q000139:chemically induced
chemical_list: D001713:Biphenyl Compounds; D002273:Carcinogens; D006873:Hydroquinones; D003577:Cytochrome P-450 Enzyme System; C004369:2-phenylphenol; C066330:phenylhydroquinone