| Official Name |
|---|
| Xanthine oxidase.
|
| Alternative Name(s) |
|---|
| Hypoxanthine oxidase. |
| Hypoxanthine-xanthine oxidase. |
| Hypoxanthine:oxygen oxidoreductase. |
| Schardinger enzyme. |
| Xanthine oxidoreductase. |
| Xanthine:O(2) oxidoreductase. |
| Xanthine:xanthine oxidase. |
| Reaction catalysed |
|---|
| Xanthine + H(2)O + O(2) <=> urate + H(2)O(2) |
| Cofactor(s) |
|---|
| FAD; Iron-sulfur; Molybdopterin.
|
| Comment(s) |
|---|
- Also oxidizes hypoxanthine, some other purines and pterins,
and aldehydes (i.e. possesses the activity of EC 1.2.3.1).
- Under some conditions the product is mainly superoxide rather than
peroxide: R-H + H(2)O + 2 O(2) = ROH + 2 O(2)(.-) + 2 H(+).
- The enzyme from animal tissues can be converted into EC 1.17.1.4.
- That from liver exists in vivo mainly as the dehydrogenase form,
but can be converted into the oxidase form by storage at -20 degrees
Celsius, by treatment with proteolytic enzymes or with organic
solvents, or by thiol reagents such as Cu(2+), N-ethylmaleamide or
4-mercuribenzoate.
- The effect of thiol reagents can be reversed by thiols such as 1,4-
dithioerythritol.
- EC 1.17.1.4 can also be converted into this enzyme by EC 1.8.4.7 in
the presence of glutathione disulfide.
- The Micrococcus enzyme can use ferredoxin as acceptor.
- Formerly EC 1.1.3.22 and EC 1.2.3.2.
|
| Cross-references |
|---|
| PROSITE | PDOC00484 |
| BRENDA | 1.17.3.2 |
| PUMA2 | 1.17.3.2 |
| PRIAM enzyme-specific profiles | 1.17.3.2 |
| KEGG Ligand Database for Enzyme Nomenclature | 1.17.3.2 |
| IUBMB Enzyme Nomenclature | 1.17.3.2 |
| IntEnz | 1.17.3.2 |
| MEDLINE | Find literature relating to 1.17.3.2 |
| MetaCyc | 1.17.3.2 |
| UniProtKB/Swiss-Prot |
|
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