“Cholesterol oxidase”的意思、由来-开放百科全书

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Cholesterol oxidase

释义

Structural studies
References
Further reading

{{enzyme
| Name = cholesterol oxidase
| EC_number = 1.1.3.6
| CAS_number = 9028-76-6
| IUBMB_EC_number = 1/1/3/6
| GO_code = 0016995
| image =
| width =
| caption =
}}{{Infobox protein family
| Symbol = Chol_subst-bind
| Name = Cholesterol oxidase substrate-binding domain
| image = PDB 1i19 EBI.jpg
| width =
| caption = crystal structure of cholesterol oxidase from b.sterolicum
| Pfam = PF09129
| Pfam_clan = CL0277
| InterPro = IPR015213
| SMART =
| PROSITE =
| MEROPS =
| SCOP = 1i19
| TCDB =
| OPM family =
| OPM protein =
| CAZy =
| CDD =
}}

In enzymology, a cholesterol oxidase ({{EC number|1.1.3.6}}) is an enzyme that catalyzes the chemical reaction

cholesterol + O₂ cholest-4-en-3-one + H₂O₂

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]

Structural studies

As of late 2007, 14 structures have been solved for this class of enzymes, with PDB accession codes {{PDB link|1B4V}}, {{PDB link|1B8S}}, {{PDB link|1CBO}}, {{PDB link|1CC2}}, {{PDB link|1COY}}, {{PDB link|1I19}}, {{PDB link|1IJH}}, {{PDB link|1MXT}}, {{PDB link|1N1P}}, {{PDB link|1N4U}}, {{PDB link|1N4V}}, {{PDB link|1N4W}}, {{PDB link|2GEW}}, and {{PDB link|3COX}}.

References

1. ^{{cite journal | vauthors = Coulombe R, Yue KQ, Ghisla S, Vrielink A | title = Oxygen access to the active site of cholesterol oxidase through a narrow channel is gated by an Arg-Glu pair | journal = J. Biol. Chem. | volume = 276 | issue = 32 | pages = 30435–41 |date=August 2001 | pmid = 11397813 | doi = 10.1074/jbc.M104103200 | url = }}

Structural studies

References

Further reading