Page last updated: 2024-10-24

squalene monooxygenase activity

Definition

Target type: molecularfunction

Catalysis of the reaction: H+ + NADPH + O2 + squalene = (S)-2,3-epoxysqualene + H2O + NADP+. [RHEA:25282]

Squalene monooxygenase (SM) is an enzyme that catalyzes the first committed step in the biosynthesis of cholesterol. This step involves the oxidation of squalene, a 30-carbon acyclic triterpene, to 2,3-oxidosqualene, a cyclic epoxide. The reaction mechanism involves the following steps: 1) Binding of squalene to the enzyme active site. 2) Activation of molecular oxygen by the enzyme, forming a reactive oxygen species. 3) Transfer of an oxygen atom from the activated oxygen species to squalene, forming 2,3-oxidosqualene. 4) Release of 2,3-oxidosqualene from the enzyme. SM is a member of the cytochrome P450 family of enzymes, which are known for their ability to catalyze a wide variety of monooxygenation reactions. SM is a highly conserved enzyme, with homologs found in all eukaryotes and some prokaryotes. The activity of SM is essential for the biosynthesis of cholesterol, which is a vital component of cell membranes and a precursor to other important steroid hormones. Mutations in the SM gene can lead to a variety of human diseases, including Smith-Lemli-Opitz syndrome, a rare genetic disorder characterized by multiple congenital anomalies. SM is also a target for the development of new drugs for the treatment of hypercholesterolemia and other diseases.'
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Proteins (1)

ProteinDefinitionTaxonomy
Squalene monooxygenaseA squalene monooxygenase that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q14534]Homo sapiens (human)

Compounds (2)

CompoundDefinitionClassesRoles
amiodaroneamiodarone : A member of the class of 1-benzofurans that is 1-benzofuran substituted by a butyl group at position 2 and a 4-[2-(diethylamino)ethoxy]-3,5-diiodobenzoyl group at position 3. It is a cardiovascular drug used for the treatment of cardiac dysrhythmias.

Amiodarone: An antianginal and class III antiarrhythmic drug. It increases the duration of ventricular and atrial muscle action by inhibiting POTASSIUM CHANNELS and VOLTAGE-GATED SODIUM CHANNELS. There is a resulting decrease in heart rate and in vascular resistance.
1-benzofurans;
aromatic ketone;
organoiodine compound;
tertiary amino compound
cardiovascular drug
terbinafineacetylenic compound;
allylamine antifungal drug;
enyne;
naphthalenes;
tertiary amine
EC 1.14.13.132 (squalene monooxygenase) inhibitor;
P450 inhibitor;
sterol biosynthesis inhibitor