151. Hydrogen peroxide-supported activities of semisynthetic flavocytochrome 2B4
- Author
-
Yuliya L. Avdeenko, Alexander I. Archakov, T. V. Bulko, Tatyana L. Moskvitina, and Victoria V. Shumyantseva
- Subjects
Clinical Biochemistry ,Anisoles ,Biochemistry ,Medicinal chemistry ,Catalysis ,law.invention ,Luminol ,chemistry.chemical_compound ,Aniline ,Cytochrome P-450 Enzyme System ,law ,Sodium Cyanide ,Glycyrrhiza ,Genetics ,Organic chemistry ,Enzyme kinetics ,Aminopyrine ,Hydrogen peroxide ,Molecular Biology ,Sodium cyanide ,Chemiluminescence ,Aniline Compounds ,Plants, Medicinal ,Proadifen ,Hydrogen Peroxide ,Cell Biology ,Aryl Hydrocarbon Hydroxylases ,Enzyme Activation ,Kinetics ,chemistry ,Luminescent Measurements ,Steroid Hydroxylases - Abstract
Semisynthetic flavocytochromes, obtained by covalent binding of riboflavin with cytochromes P450 2B4, were able to catalyze the H2O2-mediated reactions of aniline p-hydroxylation, aminopyrine N-demethylation and p-nitroanizole' O-dealkylation. The rates of the flavocytochrome-catalyzed, H2O2-supported reactions far exceeded those of the appropriate NADH-dependent reactions and were comparable with the cytochrome P450 2B4-catalyzed, peroxide-mediated reaction rates. The kinetic parameters (kcat, K(m)) for the peroxide-dependent flavocytochrome P450 2B4 reactions were obtained. Sodium cyanide and SKF-525A, a specific P450 inhibitor, were both shown to inhibit these reactions. The generation of active oxygen species by flavocytochrome 2B4 was registered by chemiluminescence intensity.
- Published
- 1998