Reaction: an ω-(methylsulfanyl)alkyl-glucosinolate + NADPH + H+ + O2 = an ω-(methylsulfinyl)alkyl-glucosinolate + NADP+ + H2O
Glossary: ω-(methylsulfanyl)alkyl-glucosinolate = an ω-(methylsulfanyl)-N-sulfo-alkylhydroximate S-glucoside
Other name(s): ω-(methylthio)alkylglucosinolate S-oxygenase; GS-OX1 (gene name)
Systematic name: ω-(methylsulfanyl)alkyl-glucosinolate,NADPH:oxygen S-oxidoreductase
Comments: The enzyme is a member of the flavin-dependent monooxygenase (FMO) family (cf. EC 1.14.13.8). The plant Arabidopsis thaliana contains five isoforms. GS-OX1 through GS-OX4 are able to catalyse the S-oxygenation independent of chain length, while GS-OX5 is specific for 8-(methylsulfanyl)octyl glucosinolate.
Links to other databases: BRENDA, EXPASY, ExplorEnz, IUBMB, KEGG, MetaCyc, CAS registry number:
References:
1. Hansen, B.G., Kliebenstein, D.J. and Halkier, B.A. Identification of a flavin-monooxygenase as the S-oxygenating enzyme in aliphatic glucosinolate biosynthesis in Arabidopsis, Plant J. 50 (2007) 902-910. [PMID: 17461789]
2. Li, J., Hansen, B.G., Ober, J.A., Kliebenstein, D.J. and Halkier, B.A. Subclade of flavin-monooxygenases involved in aliphatic glucosinolate biosynthesis. Plant Physiol. 148 (2008) 1721-1733. [PMID: 18799661]