产品内容
本酶催化的反应为Nomega-Methyl-L-Arginine + 2 NADH + 2 H+ + 3 O2 = Ndelta-Hydroxy-Nomega-Methyl-Nomega-Nitroso-L-Citrulline + 2 NAD+ + 3 H2O (Overall Reaction);;(1a) Nomega-Methyl-L-Arginine + NADH + H+ + O2 = Ndelta-Hydroxy-Nomega-Methyl-L-Arginine + NAD+ + H2O;;(1b) Ndelta-Hydroxy-Nomega-Methyl-L-Arginine + NADH + H+ + O2 = Ndelta,Nomega'-Dihydroxy-Nomega-Methyl-L-Arginine + NAD+ + H2O;;(1c) Ndelta,Nomega'-Dihydroxy-Nomega-Methyl-L-Arginine + O2 = Ndelta-Hydroxy-Nomega-Methyl-Nomega-Nitroso-L-Citrulline + H2O,系统名称为Nomega-Methyl-L-Arginine,NADH:oxygen Oxidoreductase (Ndelta-Hydroxy-Nomega-Methyl-Nomega-Nitroso-L-Citrulline-Forming),该酶从细菌 Streptomyces achromogenes 亚种 streptozoticus 中鉴定,在葡糖胺-亚硝基脲类抗生素链脲佐菌素(streptozotocin)的生物合成过程中催化复杂的多步反应。总体反应是 Nω-甲基-L-精氨酸胍基的氧化重排,生成 N-亚硝基脲产物。该酶在 Nδ 位羟化其底物,随后在 Nω' 位进行第二次羟化。然后它催化氧化重排,形成 Nδ-羟基-Nω-甲基-Nω-亚硝基-L-瓜氨酸。该产物不稳定,非酶促降解为一氧化氮和脱亚硝基产物 Nδ-羟基-Nω-甲基-L-瓜氨酸。该酶含有两个活性位点,每个活性位点利用不同的含铁辅因子。