ExplorEnz: EC 1.14.19.21

Your query returned 1 entry. Printable version

1.14.19.21

Accepted name:

cholesterol 7-desaturase

Reaction:

cholesterol + O₂ + NAD(P)H + H⁺ = cholesta-5,7-dien-3β-ol + NAD(P)⁺ + 2 H₂O

Other name(s):

nvd (gene name); daf-36 (gene name)

Systematic name:

cholesterol,NAD(P)H:oxygen oxidoreductase (7,8 dehydrogenating)

Comments:

The enzyme, characterized from several organisms including the worm Caenorhabditis elegans, the fly Drosophila melanogaster, and the ciliate Tetrahymena thermophila, is a Rieske oxygenase. In insects it participates in the the biosythesis of ecdysteroid hormones. The electrons are transferred from NAD(P)H via an electron transfer chain likely to include ferredoxin reductase and ferredoxin. The enzyme differs from regular desaturases, such as EC 1.14.19.20, 7-sterol 5(6)-desaturase, which are cytochrome b₅-dependent and contain the three His-boxes that are typical to most desaturases.

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc

References:

1.	Yoshiyama-Yanagawa, T., Enya, S., Shimada-Niwa, Y., Yaguchi, S., Haramoto, Y., Matsuya, T., Shiomi, K., Sasakura, Y., Takahashi, S., Asashima, M., Kataoka, H. and Niwa, R. The conserved Rieske oxygenase DAF-36/Neverland is a novel cholesterol-metabolizing enzyme. J. Biol. Chem. 286 (2011) 25756–25762. [DOI] [PMID: 21632547]
2.	Wollam, J., Magomedova, L., Magner, D.B., Shen, Y., Rottiers, V., Motola, D.L., Mangelsdorf, D.J., Cummins, C.L. and Antebi, A. The Rieske oxygenase DAF-36 functions as a cholesterol 7-desaturase in steroidogenic pathways governing longevity. Aging Cell 10 (2011) 879–884. [DOI] [PMID: 21749634]
3.	Najle, S.R., Nusblat, A.D., Nudel, C.B. and Uttaro, A.D. The sterol-C7 desaturase from the ciliate Tetrahymena thermophila is a Rieske oxygenase, which is highly conserved in animals. Mol. Biol. Evol. 30 (2013) 1630–1643. [DOI] [PMID: 23603937]
4.	Barry, S.M. and Challis, G.L. Mechanism and catalytic diversity of Rieske non-heme iron-dependent oxygenases. ACS Catal. 3 (2013) 2362–2370. [DOI] [PMID: 24244885]

[EC 1.14.19.21 created 2015]