title: Hydroquinone peroxidase activity of maize root mitochondria.
abstract: The oxidation of hydroquinone with H(2)O(2) in the presence of mitochondria isolated from maize (Zea mays L.) roots was studied. The results indicate that a reduced form of quinone may be a substrate of mitochondrial peroxidases. Specific activities in different mitochondrial isolates, the apparent K (m) for hydrogen peroxide and hydroquinone, and the influence of some known peroxidase inhibitors or effectors are presented. Zymographic assays revealed that all mitochondrial peroxidases, which were stained with 4-chloro-1-naphthol, were capable of oxidizing hydroquinone. A possible antioxidative role of hydroquinone peroxidase in H(2)O(2) scavenging within the mitochondria, in cooperation with ascorbate or coupled with mitochondrial NAD(P)H dehydrogenases, is proposed.
authors.affiliation: Laboratory of Plant Physiology, Maize Research Institute Zemun Polje, Belgrade.
authors.forename: Vesna
authors.initials: V
authors.lastname: Hadzi-Tasković Sukalović
authors.forename: B
authors.initials: B
authors.lastname: Kukavica
authors.forename: M
authors.initials: M
authors.lastname: Vuletić
mesh_terms: D006861:Hydrogen Peroxide / Q000378:metabolism; D006873:Hydroquinones / Q000378:metabolism*; D008928:Mitochondria / Q000201:enzymology*; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D010084:Oxidation-Reduction; D009195:Peroxidase / Q000378:metabolism*; D018517:Plant Roots / Q000201:enzymology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D003313:Zea mays / Q000201:enzymology*
chemical_list: D006873:Hydroquinones; D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide; D009195:Peroxidase; D009247:NADH, NADPH Oxidoreductases; C031927:hydroquinone