Any feedback?
Please rate this page
(literature.php)
(0/150)

BRENDA support

Literature summary extracted from

  • Kawata, S.; Traskos, J.M.; Gaylor, J.L.
    Microsomal enzymes of cholesterol biosynthesis from lanosterol. Purification and characterization of DELTA 7-sterol 5-desaturase of rat liver microsomes (1985), J. Biol. Chem., 260, 6609-6617.
    View publication on PubMed

Activating Compound

EC Number Activating Compound Comment Organism Structure
1.14.19.20 squalene and sterol carrier protein 2fold stimulation of enzyme activity in microsomes, stimulation is lower if microsomes are pretreated with phospholipase A2, acetone powder, 0.05% sodium deoxycholate or 0.2% Triton X-100 Rattus norvegicus

General Stability

EC Number General Stability Organism
1.14.19.20 extremely labile Rattus norvegicus

Inhibitors

EC Number Inhibitors Comment Organism Structure
1.14.19.20 1,10-phenanthroline 0.5 mM, 74% inhibition Rattus norvegicus
1.14.19.20 4,5-dihydroxy-1,3-benzene-disulfonic acid trivial name tiron, 0.5 mM, 80% inhibition Rattus norvegicus
1.14.19.20 bathophenanthroline 0.5 mM, 71% inhibition Rattus norvegicus
1.14.19.20 CN- 0.5 mM, 95% inhibition Rattus norvegicus
1.14.19.20 dithiothreitol 1.0 mM, 55% inhibition Rattus norvegicus

KM Value [mM]

EC Number KM Value [mM] KM Value Maximum [mM] Substrate Comment Organism Structure
1.14.19.20 0.0357
-
5alpha-Cholest-7-en-3beta-ol reconstituted enzyme system consisting of: cytochrome b5, cytochrome b5 reductase and egg lecithin liposomes Rattus norvegicus

Localization

EC Number Localization Comment Organism GeneOntology No. Textmining
1.14.19.20 microsome
-
Rattus norvegicus
-
-

Natural Substrates/ Products (Substrates)

EC Number Natural Substrates Organism Comment (Nat. Sub.) Natural Products Comment (Nat. Pro.) Rev. Reac.
1.14.19.20 5alpha-cholest-7-en-3beta-ol + 2 ferrocytochrome b5 + O2 + 2 H+ Rattus norvegicus cholesterol biosynthesis cholesta-5,7-dien-3beta-ol + 2 ferricytochrome b5 + 2 H2O
-
?

Organism

EC Number Organism UniProt Comment Textmining
1.14.19.20 Rattus norvegicus
-
multienzyme system
-

Purification (Commentary)

EC Number Purification (Comment) Organism
1.14.19.20
-
Rattus norvegicus

Source Tissue

EC Number Source Tissue Comment Organism Textmining
1.14.19.20 liver
-
Rattus norvegicus
-

Specific Activity [micromol/min/mg]

EC Number Specific Activity Minimum [µmol/min/mg] Specific Activity Maximum [µmol/min/mg] Comment Organism
1.14.19.20 0.0079
-
-
Rattus norvegicus

Storage Stability

EC Number Storage Stability Organism
1.14.19.20 0°C, 24 h, 30% loss of activity Rattus norvegicus

Substrates and Products (Substrate)

EC Number Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
1.14.19.20 5alpha-cholest-7-en-3beta-ol + 2 ferrocytochrome b5 + O2 + 2 H+ i.e. lathosterol Rattus norvegicus cholesta-5,7-dien-3beta-ol + 2 ferricytochrome b5 + 2 H2O
-
?
1.14.19.20 5alpha-cholest-7-en-3beta-ol + 2 ferrocytochrome b5 + O2 + 2 H+ enzyme is rather a mixed function oxidase which requires O2 and NAD(P)H for activity, than a dehydrogenase Rattus norvegicus cholesta-5,7-dien-3beta-ol + 2 ferricytochrome b5 + 2 H2O
-
?
1.14.19.20 5alpha-cholest-7-en-3beta-ol + 2 ferrocytochrome b5 + O2 + 2 H+ NADPH, 40% of activity with NADH Rattus norvegicus cholesta-5,7-dien-3beta-ol + 2 ferricytochrome b5 + 2 H2O
-
?
1.14.19.20 5alpha-cholest-7-en-3beta-ol + 2 ferrocytochrome b5 + O2 + 2 H+ cholesterol biosynthesis Rattus norvegicus cholesta-5,7-dien-3beta-ol + 2 ferricytochrome b5 + 2 H2O
-
?

Cofactor

EC Number Cofactor Comment Organism Structure
1.14.19.20 cytochrome b5 required as electron carrier Rattus norvegicus
1.14.19.20 NAD(P)H
-
Rattus norvegicus