Reactions of hypochlorite with catalase.
OCl-/HOCl imposed a rapid inactivation of catalase (hydrogen-peroxide: hydrogen-peroxide oxidoreductase, EC 1.11.1.6), some of which was slowly reversible upon subsequent exposure to H2O2. Ethanol accelerated this restoration of activity by H2O2. OCl- caused biphasic changes in the visible absorption spectrum of catalase, which were partially reversed by dithionite. A scheme of reactions involving axial ligation of one or two OCl- to heme iron, followed by heterolytic or homolytic cleavages of the O-Cl bond, is proposed to account for the behavior of the system.
Mashino
T
T
Department of Biochemistry, Duke University Medical Center, Durham, NC 27710.
Fridovich
I
I
D000818:Animals; D002374:Catalase / Q000037:antagonists & inhibitors*; D002417:Cattle; D000431:Ethanol / Q000494:pharmacology; D006861:Hydrogen Peroxide / Q000494:pharmacology; D006997:Hypochlorous Acid / Q000494:pharmacology*; D008099:Liver / Q000201:enzymology; D013057:Spectrum Analysis
D000431:Ethanol; D006997:Hypochlorous Acid; D006861:Hydrogen Peroxide; D002374:Catalase