MetaCyc Reaction:

Superclasses: Reactions Classified By Conversion Type Simple Reactions Chemical Reactions Composite Reactions
Reactions Classified By Substrate Small-Molecule Reactions

EC Number:

Enzymes and Genes:
valine N-monooxygenase (oxime forming) Inferred from experiment : CYP79D1 ( Manihot esculenta )
valine N-monooxygenase (oxime forming) Inferred from experiment : CYP79D2 ( Manihot esculenta )
valine N-monooxygenase (oxime forming) Inferred from experiment : CYP79D3 ( Lotus japonicus )
isoleucine N-monooxygenase (oxime forming) Inferred from experiment : CYP79D4 ( Lotus japonicus )

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the direction in which it was curated.

Most BioCyc compounds have been protonated to a reference pH value of 7.3, and some reactions have been computationally balanced for hydrogen by adding free protons. Please see the PGDB Concepts Guide for more information.

Mass balance status: Balanced.

Enzyme Commission Primary Name: valine N-monooxygenase

Enzyme Commission Synonyms: CYP79D1, CYP79D2

Taxonomic Range: Viridiplantae

L-valine + NADPH + oxygen → N-hydroxy-L-valine + NADP+ + H2O ,
N-hydroxy-L-valine + NADPH + H+ + oxygen → N,N-dihydroxy-L-valine + NADP+ + H2O ,
N,N-dihydroxy-L-valine + H+ → (E)-2-methylpropanal-oxime + CO2 + H2O

Standard Gibbs Free Energy (ΔrG in kcal/mol): -198.98792 Inferred by computational analysis [Latendresse13]

Enzyme Commission Summary:
A heme-thiolate protein (P-450). This enzyme catalyses two successive N-hydroxylations of L-valine, the first committed steps in the biosynthesis of the cyanogenic glucoside linamarin in Manihot esculenta (cassava). The product of the two hydroxylations, N,N-dihydroxy-L-valine, is extremely labile and dehydrates spontaneously. The dehydrated product is then subject to a decarboxylation that produces the oxime. It is still not known whether the decarboxylation is spontaneous or catalysed by the enzyme. The product, (E)-2-methylpropanal-oxime, undergoes a spontaneous isomerization to the (Z) form. The enzyme can also accept L-isoleucine as substrate, with a lower activity. It is different from EC (isoleucine N-monooxygenase), which prefers L-isoleucine.

Citations: [Andersen00, Forslund04]

Gene-Reaction Schematic: ?

Gene-Reaction Schematic

Unification Links: KEGG:R08663 , Rhea:28606

Relationship Links: BRENDA:EC: , ENZYME:EC: , IUBMB-ExplorEnz:EC:

Created 20-Dec-2010 by Caspi R , SRI International


Andersen00: Andersen MD, Busk PK, Svendsen I, Moller BL (2000). "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." J Biol Chem 275(3);1966-75. PMID: 10636899

Forslund04: Forslund K, Morant M, Jorgensen B, Olsen CE, Asamizu E, Sato S, Tabata S, Bak S (2004). "Biosynthesis of the nitrile glucosides rhodiocyanoside A and D and the cyanogenic glucosides lotaustralin and linamarin in Lotus japonicus." Plant Physiol 135(1);71-84. PMID: 15122013

Latendresse13: Latendresse M. (2013). "Computing Gibbs Free Energy of Compounds and Reactions in MetaCyc."

Report Errors or Provide Feedback
Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 42:D459-D471 2014
Page generated by SRI International Pathway Tools version 19.0 on Fri Mar 27, 2015, biocyc14.