Cholesterol 25-hydroxylase
In enzymology, a cholesterol 25-hydroxylase (EC 1.14.99.38) is an enzyme that catalyzes the chemical reaction
- cholesterol + AH2 + O2 25-hydroxycholesterol + A + H2O
| Cholesterol 25-hydroxylase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC number | 1.14.99.38 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| |||||||||
The 3 substrates of this enzyme are cholesterol, an electron acceptor AH2, and O2, whereas its 3 products are 25-hydroxycholesterol (25HC), the reduction product A, and H2O.
This enzyme belongs to the family of oxidoreductases, specifically those acting on paired donors, with O2 as oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derive from O miscellaneous. The systematic name of this enzyme class is cholesterol, hydrogen-donor:oxygen oxidoreductase (25-hydroxylating). This enzyme is also called cholesterol 25-monooxygenase.
Transcripts for this enzyme have been identified in macrophages from the testis.
CH25H is an interferon-stimulated gene, and its primary product 25HC may have broad-spectrum antiviral activity, demonstrated in mice against HIV, ebola, Nipah virus, and Rift Valley Fever virus.[1] Specifically, it blocks membrane fusion between the cell and virus, and may "implicate membrane-modifying oxysterols as potential antiviral therapeutics."
References
- Liu, Su-Yang; et al. (24 Jan 2013). "Interferon-Inducible Cholesterol-25-Hydroxylase Broadly Inhibits Viral Entry by Production of 25-Hydroxycholesterol". Immunity. 38 (1): 92–105. doi:10.1016/j.immuni.2012.11.005. PMC 3698975. PMID 23273844.
- Lund EG, Kerr TA, Sakai J, Li WP, Russell DW (1998). "cDNA cloning of mouse and human cholesterol 25-hydroxylases, polytopic membrane proteins that synthesize a potent oxysterol regulator of lipid metabolism". J. Biol. Chem. 273 (51): 34316–27. doi:10.1074/jbc.273.51.34316. PMID 9852097.
- Chen JJ, Lukyanenko Y, Hutson JC (2002). "25-hydroxycholesterol is produced by testicular macrophages during the early postnatal period and influences differentiation of Leydig cells in vitro". Biol. Reprod. 66 (5): 1336–41. doi:10.1095/biolreprod66.5.1336. PMID 11967195.
- Lukyanenko Y, Chen JJ, Hutson JC (2002). "Testosterone regulates 25-hydroxycholesterol production in testicular macrophages". Biol. Reprod. 67 (5): 1435–8. doi:10.1095/biolreprod.102.007575. PMID 12390873.
- Fox BG, Shanklin J, Ai J, Loehr TM, Sanders-Loehr J (1994). "Resonance Raman evidence for an Fe-O-Fe center in stearoyl-ACP desaturase. Primary sequence identity with other diiron-oxo proteins". Biochemistry. 33 (43): 12776–86. doi:10.1021/bi00209a008. PMID 7947683.
- Russell DW (2003). "The enzymes, regulation, and genetics of bile acid synthesis". Annu. Rev. Biochem. 72: 137–74. doi:10.1146/annurev.biochem.72.121801.161712. PMID 12543708.