Flavin-containing monooxygenase 5 (FMO5)

Flavin-containing monooxygenase 5 (FMO5) is a human enzyme belonging to the FMO family of NADPH-dependent flavoenzymes that catalyze the oxygenation of soft nucleophilic heteroatoms and carbonyl groups in various xenobiotic and endogenous compounds, particularly acting as a Baeyer–Villiger monooxygenase which transforms ketones into esters[1][2]. FMO5 shows higher substrate specificity for carbonyl compounds compared to other FMO isoforms; it is non- or weakly active on “classical” drug substrates but can oxidize some drugs with carbonyl groups on an aliphatic chain and acts as a positive modulator of cholesterol biosynthesis and glucose homeostasis, promoting metabolic aging[2]. Its expression is highest in adult human liver, and although not directly linked to major metabolic disorders like trimethylaminuria (more typical for FMO3), chromosomal abnormalities involving the FMO5 gene region have been reported to contribute to rare syndromes[2][1]. FMO5 may also generate reactive oxygen species under some conditions[3].

Other names

Flavin containing dimethylaniline monoxygenase 5Baeyer-Villiger monooxygenase 1Dimethylaniline monooxygenase [N-oxide-forming] 5Dimethylaniline oxidase 5NADPH oxidasehBVMO1hepatic flavin-containing monooxygenase 5

Oxygen insertion (monooxygenation) into carbonyl- or amine-bearing molecules (Baeyer–Villiger oxidation), Substrate-specific drug oxidation, NADPH oxidase activity