FMO3
Function
Essential hepatic enzyme that catalyzes the oxygenation of a wide variety of nitrogen- and sulfur-containing compounds including drugs as well as dietary compounds (PubMed:10759686, PubMed:30381441, PubMed:32156684). Plays an important role in the metabolism of trimethylamine (TMA), via the production of trimethylamine N-oxide (TMAO) metabolite (PubMed:9776311). TMA is generated by the action of gut microbiota using dietary precursors such as choline, choline containing compounds, betaine or L-carnitine. By regulating TMAO concentration, FMO3 directly impacts both platelet responsiveness and rate of thrombus formation (PubMed:29981269).
Involvement in disease
Trimethylaminuria
TMAU
Inborn error of metabolism associated with an offensive body odor and caused by deficiency of FMO-mediated N-oxidation of amino-trimethylamine (TMA) derived from foodstuffs. Affected individuals excrete relatively large amounts of TMA in their urine, sweat, and breath, and exhibit a fishy body odor characteristic of the malodorous free amine.
None
The disease is caused by variants affecting the gene represented in this entry.
Sequence Similarities
Belongs to the FMO family.
Tissue Specificity
Liver.
Cellular localization
- Microsome membrane
- Single-pass membrane protein
- Endoplasmic reticulum membrane
- Single-pass membrane protein
Alternative names
Flavin-containing monooxygenase 3, Dimethylaniline monooxygenase [N-oxide-forming] 3, Dimethylaniline oxidase 3, FMO II, FMO form 2, Hepatic flavin-containing monooxygenase 3, Trimethylamine monooxygenase, FMO 3, FMO3