Xanthine Oxidase

Xanthine oxidase (XO, sometimes 'XAO') is a form of xanthine oxidoreductase, an enzyme that generates reactive oxygen species. It catalyzes the oxidation of hypoxanthine to xanthine and can further catalyze the oxidation of xanthine to uric acid. This enzyme plays an important role in the catabolism of purines in some species, including humans.

Xanthine oxidase 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 xanthine dehydrogenase activity (EC 1.17.1.4). Most of the protein in the liver exists in a form with xanthine dehydrogenase activity, but it can be converted to xanthine oxidase by reversible sulfhydryl oxidation or by irreversible proteolytic modification.

Read more about Xanthine OxidaseReaction, Protein Structure, Catalytic Mechanism, Clinical Significance, Inhibitors

Other articles related to "xanthine oxidase, oxidase, xanthine":

Tioguanine - Metabolism and Pharmacokinetics
... which has minimal anti-neoplastic activity, then by oxidation by xanthine oxidase of the thioxanthine to thiouric acid ... pathway is not dependent on the efficacy of xanthine oxidase, so that the inhibitor of xanthine oxidase, the drug allopurinol, does not block the breakdown of ... This pathway also is independent of the enzyme activity of xanthine oxidase ...
Hyperuricemia - Treatment - Concentration
... often used to treat hyperuricemia are of two kinds xanthine oxidase inhibitors and uricosurics ... Xanthine oxidase inhibitors decrease the production of uric acid, by interfering with xanthine oxidase ...
Molybdenum - Biological Role - Biochemistry
... and their number is increasing with every year those enzymes include aldehyde oxidase, sulfite oxidase and xanthine oxidase ... In some animals, and in humans, the oxidation of xanthine to uric acid, a process of purine catabolism, is catalyzed by xanthine oxidase, a molybdenum-containing enzyme ... The activity of xanthine oxidase is directly proportional to the amount of molybdenum in the body ...
Allopurinol - Mechanism of Action
... in the body) and is an inhibitor of the enzyme xanthine oxidase ... Xanthine oxidase is responsible for the successive oxidation of hypoxanthine and xanthine, resulting in the production of uric acid, the product of human purine metabolism ... In addition to blocking uric acid production, inhibition of xanthine oxidase causes an increase in hypoxanthine and xanthine ...