title: Role of the prosthetic groups of NADPH-cytochrome P450 reductase in 3-hydroxyanthranilamide-catalyzed, NADPH-dependent superoxide anion production.
abstract: The role of the prosthetic groups (FAD and FMN) of NADPH-cytochrome P450 reductase (P450 reductase)in 3-hydroxyanthranilamide (3-OH An.Amide)-catalyzed, NADPH-dependent superoxide anion (O2-) production via the reductase was examined using the native and FMN-depleted preparations of P450 reductase which was partially purified from rat liver microsomes. NADPH-dependent O2-production by the FMN-depleted preparation was about 10% of that by the native preparation. 3-OH An. Amide-catalyzed, NADPH-dependent O2-production by the FMN-depleted preparation was less than 10% of that by the native preparation. FMN supplementation returned O2-production to near normal. We observed the same results for NADPH oxidation and hydrogen peroxide formation. O2-production, NADPH oxidation, and hydrogen peroxide formation were inhibited by native superoxide dismutase (SOD), but not by boiled, denatured SOD. These results indicate that the prosthetic groups, especially FMN, of P450 reductase play a critical role in 3-OH An.Amide-catalyzed, NADPH-dependent O2-production via the reductase.
authors.affiliation: a Department of Biochemistry , School of Medicine, Fujita Health University , Toyoake , Aichi , Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Ohta
authors.affiliation: b Department of Biochemistry , School of Health Sciences, Fujita Health University , Toyoake , Aichi , Japan.
authors.forename: R
authors.initials: R
authors.lastname: Shinohara
authors.affiliation: a Department of Biochemistry , School of Medicine, Fujita Health University , Toyoake , Aichi , Japan.
authors.forename: I
authors.initials: I
authors.lastname: Ishiguro