FMO2
Description
The FMO2 (flavin containing dimethylaniline monoxygenase 2) is a protein-coding gene located on chromosome 1.
Dimethylaniline monooxygenase [N-oxide-forming] 2 is an enzyme encoded by the FMO2 gene in humans. Flavin-containing monooxygenases are NADPH-dependent enzymes that catalyze the oxidation of numerous drugs and xenobiotics. In most mammals, a flavin-containing monooxygenase catalyzes N-oxidation of some primary alkylamines through an N-hydroxylamine intermediate. However, in humans, this enzyme is truncated and likely rapidly degraded. The protein encoded by FMO2 represents the truncated form and appears to lack catalytic activity. A functional allele found in African Americans has been reported, but no sequence evidence has been deposited to support this finding. FMO2 is located in a cluster with the FMO1, FMO3, and FMO4 genes on chromosome 1.
FMO2 catalyzes the oxidative metabolism of various xenobiotics, primarily therapeutic drugs and insecticides containing soft nucleophiles, especially nitrogen and sulfur, contributing to their bioactivation. It specifically catalyzes S-oxygenation of sulfur-derived compounds, such as thioureas and thioetherorganophosphates, to their sulfenic acid. In vitro, FMO2 catalyzes S-oxygenation of the second-line antitubercular drugs thiacetazone (TAZ) and ethionamide (ETA), forming a sulfinic acid and a carbodiimide via a postulated sulfenic acid intermediate. Additionally, it catalyzes S-oxygenation of the thioether-containing organophosphate insecticides, phorate and disulfoton.
FMO2 is also known as FMO1B1.
