title: Nonenzymatic reduction of brucine N-oxide by the heme group of cytochrome P450.
abstract: Evidence showing that cytochrome P450-mediated reduction of brucine N-oxide to brucine by rat liver microsomes proceeds nonenzymatically in the presence of both a reduced pyridine nucleotide and FAD is presented. The microsomal N-oxide reduction appears to proceed in two steps: The first step is reduction of FAD by NADPH or NADH either enzymatically or nonenzymatically. The second step is nonenzymatic reduction of the tertiary amine N-oxide by the reduced flavin and is nonenzymatically catalyzed by the heme group of cytochrome P450.
authors.affiliation: Institute of Pharmaceutical Science, Hiroshima University School of Medicine, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Takekawa
authors.forename: K
authors.initials: K
authors.lastname: Sugihara
authors.forename: S
authors.initials: S
authors.lastname: Kitamura
authors.forename: K
authors.initials: K
authors.lastname: Tatsumi
mesh_terms: D000818:Animals; D003497:Cyclic N-Oxides / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry / Q000378:metabolism*; D006418:Heme / Q000378:metabolism; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism*; D011487:Protein Conformation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013331:Strychnine / Q000031:analogs & derivatives* / Q000378:metabolism
chemical_list: D003497:Cyclic N-Oxides; C083067:brucine N-oxide; D006418:Heme; D003577:Cytochrome P-450 Enzyme System; D013331:Strychnine