Oxidoreductases;
Acting on paired donors, with incorporation or reduction of molecular oxygen;
With reduced flavin or flavoprotein as one donor, and incorporation of one atom of oxygen into the other donor
BRITE hierarchy

L-valine,[reduced NADPH---hemoprotein reductase]:oxygen oxidoreductase (N-hydroxylating)

L-valine + 2 [reduced NADPH---hemoprotein reductase] + 2 O2 = (E)-2-methylpropanal oxime + 2 [oxidized NADPH---hemoprotein reductase] + CO2 + 3 H2O (overall reaction) [RN:R08663];
(1a) L-valine + [reduced NADPH---hemoprotein reductase] + O2 = N-hydroxy-L-valine + [oxidized NADPH---hemoprotein reductase] + H2O [RN:R10031];
(1b) N-hydroxy-L-valine + [reduced NADPH---hemoprotein reductase] + O2 = N,N-dihydroxy-L-valine + [oxidized NADPH---hemoprotein reductase] + H2O [RN:R10032];
(1c) N,N-dihydroxy-L-valine = (E)-2-methylpropanal oxime + CO2 + H2O [RN:R10033]

R08663 R10031 R10032 R10033;
(other) R10027 R10028 R10029
Reaction

L-valine [CPD:C00183];
[reduced NADPH---hemoprotein reductase] [CPD:C03024];
O2 [CPD:C00007];
N-hydroxy-L-valine [CPD:C20313];
N,N-dihydroxy-L-valine [CPD:C20314]

A cytochrome P-450 (heme-thiolate) protein. This enzyme catalyses two successive N-hydroxylations of L-valine, the committed step in the biosynthesis of the cyanogenic glucoside linamarin in Manihot esculenta (cassava). The product of the two hydroxylations, N,N-dihydroxy-L-valine, is labile and undergoes dehydration and decarboxylation that produce the (E) isomer of the oxime. It is still not known whether the decarboxylation is spontaneous or catalysed by the enzyme. The enzyme can also accept L-isoleucine as substrate, with a lower activity. It is different from EC 1.14.14.39, isoleucine N-monooxygenase, which prefers L-isoleucine.

EC 1.14.14.38 created 2010 as EC 1.14.13.118, transferred 2017 to EC 1.14.14.38

1  [PMID:10636899]

2  [PMID:15122013]