title: 4-Nitrobenzoic acid reductase of Ascaris lumbricoides var suum. Substrate specificity and reaction products.
abstract: 1. The substrate specificity of nitro-reductase from Ascaris lumbricoides varsum was determined. This enzyme reduced nitrobenzene, 4-nitrohippuric acid and the isomers of nitrophenol, nitroanisole, nitrobenzoic acid, nitrobenzaldehyde and nitrobenzyl alcohol. The same enzyme preparation reduced azobenzene, 4-dimethylaminoazobenzene and 1,2-dimethyl-4-(4-carboxyphenylazo)-5-hydroxybenzene. Nitrobenzaldehyde isomers were not reduced to the alcohols. 2. The products of nitro- and azo-reduction were the corresponding amines, no hydroxylamino or hydrazo compounds were detected. 3. The pH optima and cofactor requirements were the same for both azo- and nitro-reduction and neither reaction was inhibited by oxygen. 4. Ammonium sulphate fractionation failed to separate azo- and nitro-reductase activities. The molecular weight of both azo- and nitro-reductase was about 130 000.
mesh_terms: D000588:Amines / Q000096:biosynthesis; D062365:Aminobenzoates / Q000096:biosynthesis; D000645:Ammonium Sulfate; D000818:Animals; D000840:Anisoles / Q000378:metabolism; D001200:Ascaris / Q000201:enzymology*; D001555:Benzene Derivatives / Q000378:metabolism*; D001565:Benzoates / Q000378:metabolism*; D005591:Chemical Fractionation; D002850:Chromatography, Gel; D002855:Chromatography, Thin Layer; D008970:Molecular Weight; D009243:NAD / Q000378:metabolism; D009574:Nitro Compounds; D009578:Nitrobenzenes / Q000378:metabolism; D009579:Nitrobenzoates / Q000378:metabolism; D009596:Nitrophenols / Q000378:metabolism; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000378:metabolism*; D004124:p-Dimethylaminoazobenzene / Q000378:metabolism
chemical_list: D000588:Amines; D062365:Aminobenzoates; D000840:Anisoles; D001555:Benzene Derivatives; D001565:Benzoates; D009574:Nitro Compounds; D009578:Nitrobenzenes; D009579:Nitrobenzoates; D009596:Nitrophenols; D009243:NAD; D004124:p-Dimethylaminoazobenzene; D010088:Oxidoreductases; D000645:Ammonium Sulfate