Reaction: an L-polyhomomethionine + 2 O2 + 2 [reduced NADPHhemoprotein reductase] = an ω-(methylsulfanyl)-(E)-alkanal oxime + CO2 + 3 H2O + 2 [oxidized NADPHhemoprotein reductase] (overall reaction)
(1a) an L-polyhomomethionine + O2 + [reduced NADPHhemoprotein reductase] = an L-N-hydroxypolyhomomethionine + H2O + [oxidized NADPHhemoprotein reductase]
(1b) an L-N-hydroxypolyhomomethionine + O2 + [reduced NADPHhemoprotein reductase] = an L-N,N-dihydroxypolyhomomethionine + H2O + [oxidized NADPHhemoprotein reductase]
(1c) an L-N,N-dihydroxypolyhomomethionine = ω-(methylsulfanyl)-(E)-alkanal oxime + CO2 + H2O
Other name(s): CYP79F1 (gene name); CYP79F2 (gene name)
Glossary: homomethionine = (2S)-2-amino-5-(methylsulfanyl)pentanoate
an L-polyhomomethionine = analogs of L-methionine that contain additional methylene groups in the side chain prior to the sulfur atom.
Systematic name: L-homomethionine,[NADPHhemoprotein reductase]:oxygen oxidoreductase
Comments: This plant cytochrome P-450 (heme thiolate) enzyme is involved in methionine-derived aliphatic glucosinolates biosynthesis. It catalyses two successive N-hydroxylations, which are followed by dehydration and decarboxylation. CYP79F1 from Arabidopsis thaliana can metabolize homo-, di-, tri-, tetra-, penta-, and hexahomomethionine to their corresponding aldoximes, while CYP79F2 from the same plant can only metabolize penta- and hexahomomethionine.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
1. Hansen, C.H., Wittstock, U., Olsen, C.E., Hick, A.J., Pickett, J.A. and Halkier, B.A. Cytochrome p450 CYP79F1 from Arabidopsis catalyzes the conversion of dihomomethionine and trihomomethionine to the corresponding aldoximes in the biosynthesis of aliphatic glucosinolates. J. Biol. Chem. 276 (2001) 11078-11085. [PMID: 11133994]
2. Chen, S., Glawischnig, E., Jørgensen, K., Naur, P., Jorgensen, B., Olsen, C.E., Hansen, C.H., Rasmussen, H., Pickett, J.A. and Halkier, B.A. CYP79F1 and CYP79F2 have distinct functions in the biosynthesis of aliphatic glucosinolates in Arabidopsis. Plant J. 33 (2003) 923-937. [PMID: 12609033]