Δ7-sterol 5(6)-desaturase

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Ketiltrout (talk | contribs) at 23:07, 20 July 2016 (dab). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Lathosterol oxidase
Identifiers
EC no.1.14.21.6
CAS no.37255-37-1
Databases
IntEnzIntEnz view
BRENDABRENDA entry
ExPASyNiceZyme view
KEGGKEGG entry
MetaCycmetabolic pathway
PRIAMprofile
PDB structuresRCSB PDB PDBe PDBsum
Search
PMCarticles
PubMedarticles
NCBIproteins

In enzymology, a lathosterol oxidase (EC 1.14.21.6) is an enzyme that catalyzes the chemical reaction

5alpha-cholest-7-en-3beta-ol + NAD(P)H + H+ + O2 cholesta-5,7-dien-3beta-ol + NAD(P)+ + 2 H2O

The 5 substrates of this enzyme are 5alpha-cholest-7-en-3beta-ol, NADH, NADPH, H+, and O2, whereas its 4 products are cholesta-5,7-dien-3beta-ol, NAD+, NADP+, and H2O.

Classification

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 derived from O2 with NADH or NADPH as one donor, and the other dehydrogenated.

Nomenclature

The systematic name of this enzyme class is 5alpha-cholest-7-en-3beta-ol,NAD(P)H:oxygen 5-oxidoreductase. Other names in common use include Delta7-sterol Delta5-dehydrogenase, Delta7-sterol 5-desaturase, Delta7-sterol-C5(6)-desaturase, and 5-DES.

Biological role

This enzyme participates in biosynthesis of steroids. It has 2 cofactors: FAD, and FMN.

References

  • DEMPSEY ME, SEATON JD, SCHROEPFER GJ, TROCKMAN RW (1964). "THE INTERMEDIARY ROLE OF DELTA-5,7-CHOLESTADIEN-3-BETA-OL IN CHOLESTEROL BIOSYNTHESIS". J. Biol. Chem. 239: 1381–7. PMID 14189869.
  • Nishino H, Nakaya J, Nishi S, Kurosawa T, Ishibashi T (1997). "Temperature-induced differential kinetic properties between an initial burst and the following steady state in membrane-bound enzymes: studies on lathosterol 5-desaturase". Arch. Biochem. Biophys. 339 (2): 298–304. doi:10.1006/abbi.1996.9871. PMID 9056262.
  • Taton M, Rahier A (1996). "Plant sterol biosynthesis: identification and characterization of higher plant delta 7-sterol C5(6)-desaturase". Arch. Biochem. Biophys. 325 (2): 279–88. doi:10.1006/abbi.1996.0035. PMID 8561508.
  • Taton M, Husselstein T, Benveniste P, Rahier A (2000). "Role of highly conserved residues in the reaction catalyzed by recombinant Delta7-sterol-C5(6)-desaturase studied by site-directed mutagenesis". Biochemistry. 39 (4): 701–11. doi:10.1021/bi991467t. PMID 10651635.