title: Single electron reduction of xenobiotic compounds by glucose oxidase from Aspergillus niger.
abstract: Various species of fungi express glucose oxidase that catalyzes formation of gluconolactone from glucose with concomitant, direct divalent reduction of molecular oxygen to hydrogen peroxide. A physiological function ascribed to this extracellular enzyme is production of hydrogen peroxide for use in lignin degradation catalyzed by lignin peroxidases. Herein, we show that glucose oxidase can catalyze one-electron reduction of several different classes of xenobiotic compounds resulting in generation of free radical products. Electron spin resonance (ESR) spectroscopy was used to visualize the one-electron reduction products of 4-nitropyridine-N-oxide (4NPO), 1,4-naphthoquinone (1,4NQ), and dichlorophenolindolphenol (DCPIP). Hyperfine splitting constants were used to generate computer simulations of the spectra confirming the presence of free radical products.
authors.affiliation: Department of Biochemistry, Louisiana State University, Baton Rouge 70803, USA.
authors.forename: C A
authors.initials: CA
authors.lastname: Metosh-Dickey
authors.forename: R P
authors.initials: RP
authors.lastname: Mason
authors.forename: G W
authors.initials: GW
authors.lastname: Winston
mesh_terms: D001234:Aspergillus niger / Q000187:drug effects* / Q000201:enzymology; D002384:Catalysis; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D005949:Glucose Oxidase / Q000187:drug effects*; D010084:Oxidation-Reduction; D015262:Xenobiotics / Q000494:pharmacology*
chemical_list: D005609:Free Radicals; D015262:Xenobiotics; D005949:Glucose Oxidase