Reaction: (1) (E)-2-methylbutanal oxime + [reduced NADPH—hemoprotein reductase] + O2 = 2-hydroxy-2-methylbutanenitrile + [oxidized NADPH—hemoprotein reductase] + 2 H2O (overall reaction)
(1a) (E)-2-methylbutanal oxime = (Z)-2-methylbutanal oxime
(1b) (Z)-2-methylbutanal oxime = 2-methylbutanenitrile + H2O
(1c) 2-methylbutanenitrile + [reduced NADPH—hemoprotein reductase] + O2 = 2-hydroxy-2-methylbutanenitrile + [oxidized NADPH—hemoprotein reductase] + H2O
(2) (E)-2-methylpropanal oxime + [reduced NADPH—hemoprotein reductase] + O2 = 2-hydroxy-2-methylpropanenitrile + [oxidized NADPH—hemoprotein reductase] + 2 H2O (overall reaction)
(2a) (E)-2-methylpropanal oxime = (Z)-2-methylpropanal oxime
(2b) (Z)-2-methylpropanal oxime = 2-methylpropanenitrile + H2O
(2c) 2-methylpropanenitrile + [reduced NADPH—hemoprotein reductase] + O2 = 2-hydroxy-2-methylpropanenitrile + [oxidized NADPH—hemoprotein reductase] + H2O
Other name(s): CYP71E7 (gene name)
Systematic name: (E)-2-methylbutanal oxime,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase
Comments: This cytochrome P-450 (heme thiolate) enzyme is involved in the biosynthesis of the cyanogenic glucosides lotaustralin and linamarin. It catalyses three different activities - isomerization of its substrate, the (E) isomer, to the (Z) isomer, dehydration, and C-hydroxylation.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Jørgensen, K., Morant, A.V., Morant, M., Jensen, N.B., Olsen, C.E., Kannangara, R., Motawia, M.S., Møller, B.L. and Bak, S. Biosynthesis of the cyanogenic glucosides linamarin and lotaustralin in cassava: isolation, biochemical characterization, and expression pattern of CYP71E7, the oxime-metabolizing cytochrome P450 enzyme. Plant Physiol. 155 (2011) 282-292. [PMID: 21045121]