Preparation of bovine milk xanthine oxidase as a dehydrogenase form.

摘要: When xanthine oxidase was prepared from fresh raw cow's milk in the presence of dithioerythritol, 94% its xanthine-oxidizing activity found as a dehydrogenase type. The enzyme reversibly converted to an type when dithioerythritol removed. conversion ascribable oxidation sulfhydryl groups by oxygen. two forms gave same visible spectrum, but form alone characteristic difference spectrum upon addition NAD+. NADH served good electron donor for not form. used donor, overall rate p-benzoquinone reduction and forms, proportion one-electron flux considerably greater reaction than that