<unk>  <unk> , sometimes XAO) is a form of<unk>  oxidoreductase, a type of enzyme that generates reactive oxygen species. These enzymes catalyze the oxidation of hypoxanthine to<unk>  and can further catalyze the oxidation of<unk>  to uric acid. These enzymes play an important role in the catabolism of purines in some species, including humans.<unk>  is defined as an enzyme activity (EC 1.17.3.2). The same protein, which in humans has the HGNC approved gene symbol XDH, can also have<unk>  dehydrogenase activity (EC 1.17.1.4). Most of the protein in the liver exists in a form with<unk>  dehydrogenase activity, but it can be converted to<unk>  by reversible sulfhydryl oxidation or by irreversible proteolytic modification.
Xanthine oxidase
Aldehyde oxidase
Thymidine phosphorylase
Aldehyde dehydrogenase
Transaminase
Biotinidase
Phenylalanine hydroxylase
Asparaginase