KEGG   ENZYME: 1.14.14.39Help
Entry
EC 1.14.14.39               Enzyme                                 

Name
isoleucine N-monooxygenase;
CYP79D3 (gene name);
CYP79D4 (gene name)
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-isoleucine,[reduced NADPH---hemoprotein reductase]:oxygen oxidoreductase (N-hydroxylating)
Reaction(IUBMB)
L-isoleucine + 2 [reduced NADPH---hemoprotein reductase] + 2 O2 = (1E,2S)-2-methylbutanal oxime + 2 [oxidized NADPH---hemoprotein reductase] + CO2 + 3 H2O (overall reaction) [RN:R09403];
(1a) L-isoleucine + [reduced NADPH---hemoprotein reductase] + O2 = N-hydroxy-L-isoleucine + [oxidized NADPH---hemoprotein reductase] + H2O [RN:R10027];
(1b) N-hydroxy-L-isoleucine + [reduced NADPH---hemoprotein reductase] + O2 = N,N-dihydroxy-L-isoleucine + [oxidized NADPH---hemoprotein reductase] + H2O [RN:R10028];
(1c) N,N-dihydroxy-L-isoleucine = (1E,2S)-2-methylbutanal oxime + CO2 + H2O (spontaneous) [RN:R10029]
Reaction(KEGG)
Substrate
L-isoleucine [CPD:C00407];
[reduced NADPH---hemoprotein reductase] [CPD:C03024];
O2 [CPD:C00007];
N-hydroxy-L-isoleucine [CPD:C20310];
N,N-dihydroxy-L-isoleucine [CPD:C20311]
Product
(1E,2S)-2-methylbutanal oxime;
[oxidized NADPH---hemoprotein reductase] [CPD:C03161];
CO2 [CPD:C00011];
H2O [CPD:C00001];
N-hydroxy-L-isoleucine [CPD:C20310];
N,N-dihydroxy-L-isoleucine [CPD:C20311]
Comment
This cytochrome P-450 (heme-thiolate) enzyme, found in plants, catalyses two successive N-hydroxylations of L-isoleucine, the committed step in the biosynthesis of the cyanogenic glucoside lotaustralin. The product of the two hydroxylations, N,N-dihydroxy-L-isoleucine, is labile and undergoes dehydration followed by decarboxylation, producing the oxime. It is still not known whether the decarboxylation is spontaneous or catalysed by the enzyme. The enzyme can also accept L-valine, but with a lower activity. cf. EC 1.14.14.38, valine N-monooxygenase.
History
EC 1.14.14.39 created 2010 as EC 1.14.13.117, transferred 2017 to EC 1.14.14.39
Pathway
ec00460  Cyanoamino acid metabolism
ec00966  Glucosinolate biosynthesis
ec01100  Metabolic pathways
ec01110  Biosynthesis of secondary metabolites
Orthology
K14984  isoleucine N-monooxygenase
Genes
LJA: Lj3g3v0755150.1(Lj3g3v0755150.1)
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
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
  Sequence
Other DBs
ExplorEnz - The Enzyme Database: 1.14.14.39
IUBMB Enzyme Nomenclature: 1.14.14.39
ExPASy - ENZYME nomenclature database: 1.14.14.39
BRENDA, the Enzyme Database: 1.14.14.39
LinkDB All DBs

DBGET integrated database retrieval system