KEGG   ENZYME: 1.14.14.38Help
Entry
EC 1.14.14.38               Enzyme                                 

Name
valine N-monooxygenase;
CYP79D1;
CYP79D2
Class
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
Sysname
L-valine,[reduced NADPH---hemoprotein reductase]:oxygen oxidoreductase (N-hydroxylating)
Reaction(IUBMB)
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]
Reaction(KEGG)
Substrate
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]
Product
(E)-2-methylpropanal oxime [CPD:C03219];
[oxidized NADPH---hemoprotein reductase] [CPD:C03161];
CO2 [CPD:C00011];
H2O [CPD:C00001];
N-hydroxy-L-valine [CPD:C20313];
N,N-dihydroxy-L-valine [CPD:C20314]
Comment
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.
History
EC 1.14.14.38 created 2010 as EC 1.14.13.118, transferred 2017 to EC 1.14.14.38
Pathway
ec00460  Cyanoamino acid metabolism
ec00966  Glucosinolate biosynthesis
ec01100  Metabolic pathways
ec01110  Biosynthesis of secondary metabolites
Orthology
K13401  valine N-monooxygenase
Genes
RCU: 8273208
JCU: 105641619
HBR: 110641550
MESC: 110627795 110629733
Taxonomy
Reference
1  [PMID:10636899]
  Authors
Andersen MD, Busk PK, Svendsen I, Moller BL
  Title
Cytochromes P-450 from cassava (Manihot esculenta Crantz) catalyzing the first steps in the biosynthesis of the cyanogenic glucosides linamarin and lotaustralin. Cloning, functional expression in Pichia pastoris, and substrate specificity of the isolated recombinant enzymes.
  Journal
J Biol Chem 275:1966-75 (2000)
DOI:10.1074/jbc.275.3.1966
  Sequence
Reference
2  [PMID:15122013]
  Authors
Forslund K, Morant M, Jorgensen B, Olsen CE, Asamizu E, Sato S, Tabata S, Bak S
  Title
Biosynthesis of the nitrile glucosides rhodiocyanoside A and D and the cyanogenic glucosides lotaustralin and linamarin in Lotus japonicus.
  Journal
Plant Physiol 135:71-84 (2004)
DOI:10.1104/pp.103.038059
Other DBs
ExplorEnz - The Enzyme Database: 1.14.14.38
IUBMB Enzyme Nomenclature: 1.14.14.38
ExPASy - ENZYME nomenclature database: 1.14.14.38
BRENDA, the Enzyme Database: 1.14.14.38
LinkDB All DBs

DBGET integrated database retrieval system