Flavin monooxygenase (FMO) 5 (IPR002257)

Short name: Flavin_mOase_5

Overlapping homologous superfamilies


Family relationships


Flavin-containing monooxygenases (FMOs) constitute a family of xenobiotic- metabolising enzymes [PMID: 8311461]. Using an NADPH cofactor and FAD prosthetic group, these microsomal proteins catalyse the oxygenation of nucleophilic nitrogen, sulphur, phosphorous and selenium atoms in a range of structurally diverse compounds. Five mammalian forms of FMO are now known and have been designated FMO1-FMO5 [PMID: 1712018, PMID: 2318837, PMID: 1542660, PMID: 1417778, PMID: 8486656].

The deduced amino acid sequence of human FM05 includes the putative FAD- (GxGxxG) and NADP+ pyrophosphate-binding (GxGxxA) sites characteristic of mammalian FMOs [PMID: 9580872], a 'FATGY' motif that has also been observed in a range of siderphore biosynthetic enzymes [PMID: 9538688], and a C-terminal hydrophobic segment that is believed to anchor the monooxygenase to the microsomal membrane [PMID: 2355001]. Human and guinea pig FMO5, like other FMOs, are encoded by multiple transcripts. FMO5 has been identified in livers of adult humans, rabbits and guinea pigs, and foetal livers of humans [PMID: 7872795]. Neither the human nor guinea pig enzyme effectively catalyse the metabolism of methimazole, a general FMO substrate; however, both are active with n-octylamine [PMID: 7872795]. The responses to detergent, ions and elevated temperature are all similar to those observed in rabbit FMO5, suggesting that these properties are species- independent and that this form of FMO is not readily classified as a drug- metabolising enzyme [PMID: 7872795].

GO terms

Biological Process

GO:0055114 oxidation-reduction process

Molecular Function

GO:0004499 N,N-dimethylaniline monooxygenase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.