| cholesterol oxidase | |
| Ec Number: | 1.1.3.6 |
| Cas Number: | 9028-76-6 |
| Go Code: | 0016995 |
| Symbol: | Chol_subst-bind |
| Cholesterol oxidase substrate-binding domain | |
| Pfam: | PF09129 |
| Pfam Clan: | CL0277 |
| Interpro: | IPR015213 |
| Scop: | 1i19 |
In enzymology, a cholesterol oxidase is an enzyme that catalyzes the chemical reaction
cholesterol + O2
\rightleftharpoons
Thus, the two substrates of this enzyme are cholesterol and O2, whereas its two products are cholest-4-en-3-one and H2O2.
This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with oxygen as acceptor. The systematic name of this enzyme class is cholesterol:oxygen oxidoreductase. Other names in common use include cholesterol- O2 oxidoreductase, 3beta-hydroxy steroid oxidoreductase, and 3beta-hydroxysteroid:oxygen oxidoreductase. This enzyme participates in bile acid biosynthesis.
The substrate-binding domain found in some bacterial cholesterol oxidases is composed of an eight-stranded mixed beta-pleated sheet and six alpha-helices. This domain is positioned over the isoalloxazine ring system of the FAD cofactor bound by the FAD-binding domain and forms the roof of the active site cavity, allowing for catalysis of oxidation and isomerisation of cholesterol to cholest-4-en-3-one.[1]
As of late 2007, 14 structures have been solved for this class of enzymes, with PDB accession codes,,,,,,,,,,,,, and .