Entry
Name
aromatic aldoxime N-monooxygenase;
CYP83B1 (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
(E)-indol-3-ylacetaldoxime,[reduced NADPH---hemoprotein reductase],glutathione:oxygen oxidoreductase (oxime-hydroxylating)
Reaction(IUBMB)
(1) (E)-indol-3-ylacetaldehyde oxime + [reduced NADPH---hemoprotein reductase] + glutathione + O2 = S-[(E)-N-hydroxy(indol-3-yl)acetimidoyl]-L-glutathione + [oxidized NADPH---hemoprotein reductase] + 2 H2O (overall reaction) [RN:
R11734 ];
(1a) (E)-indol-3-ylacetaldehyde oxime + [reduced NADPH---hemoprotein reductase] + O2 = 1-(1H-indol-3-yl)-2-aci-nitroethane + [oxidized NADPH---hemoprotein reductase] + H2O [RN:
R11735 ];
(1b) 1-(1H-indol-3-yl)-2-aci-nitroethane + glutathione = S-[(E)-N-hydroxy(indol-3-yl)acetimidoyl]-L-glutathione + H2O (spontaneous) [RN:
R11736 ];
(2) (E)-phenylacetaldehyde oxime + [reduced NADPH---hemoprotein reductase] + glutathione + O2 = S-[(Z)-N-hydroxy(phenyl)acetimidoyl]-L-glutathione + [oxidized NADPH---hemoprotein reductase] + 2 H2O (overall reaction) [RN:
R11737 ];
(2a) (E)-phenylacetaldehyde oxime + [reduced NADPH---hemoprotein reductase] + O2 = 1-aci-nitro-2-phenylethane + [oxidized NADPH---hemoprotein reductase] + H2O [RN:
R11738 ];
(2b) 1-aci-nitro-2-phenylethane + glutathione = S-[(Z)-N-hydroxy(phenyl)acetimidoyl]-L-glutathione + H2O (spontaneous) [RN:
R11739 ]
Reaction(KEGG)
Substrate
(E)-indol-3-ylacetaldehyde oxime;
[reduced NADPH---hemoprotein reductase] [CPD:
C03024 ];
glutathione [CPD:
C00051 ];
O2 [CPD:
C00007 ];
1-(1H-indol-3-yl)-2-aci-nitroethane [CPD:
C17204 ];
(E)-phenylacetaldehyde oxime [CPD:
C19714 ];
1-aci-nitro-2-phenylethane [CPD:
C21623 ]
Product
S-[(E)-N-hydroxy(indol-3-yl)acetimidoyl]-L-glutathione [CPD:
C21620 ];
[oxidized NADPH---hemoprotein reductase] [CPD:
C03161 ];
H2O [CPD:
C00001 ];
1-(1H-indol-3-yl)-2-aci-nitroethane [CPD:
C17204 ];
S-[(Z)-N-hydroxy(phenyl)acetimidoyl]-L-glutathione [CPD:
C21622 ];
1-aci-nitro-2-phenylethane [CPD:
C21623 ]
Comment
This cytochrome P-450 (heme thiolate) enzyme is involved in the biosynthesis of glucosinolates in plants. The enzyme catalyses the N-hydroxylation of aromatic aldoximes derived from L-tryptophan, L-phenylalanine, and L-tyrosine, forming an aci-nitro intermediate that reacts non-enzymically with glutathione to produce an N-alkyl-thiohydroximate adduct, the committed precursor of glucosinolates. In the absence of glutathione, the enzyme is suicidal, probably due to interaction of the reactive aci-nitro compound with catalytic residues in the active site.
History
EC 1.14.14.45 created 2017
Pathway
ec01110 Biosynthesis of secondary metabolites
Orthology
K11818 aromatic aldoxime N-monooxygenase
Genes
CSAT : 104721689 104727643 104730102
» show all
Taxonomy
Reference
Authors
Bak S, Tax FE, Feldmann KA, Galbraith DW, Feyereisen R
Title
CYP83B1, a cytochrome P450 at the metabolic branch point in auxin and indole glucosinolate biosynthesis in Arabidopsis.
Journal
Reference
Authors
Naur P, Petersen BL, Mikkelsen MD, Bak S, Rasmussen H, Olsen CE, Halkier BA
Title
CYP83A1 and CYP83B1, two nonredundant cytochrome P450 enzymes metabolizing oximes in the biosynthesis of glucosinolates in Arabidopsis.
Journal
Reference
Authors
Geu-Flores F, Moldrup ME, Bottcher C, Olsen CE, Scheel D, Halkier BA
Title
Cytosolic gamma-glutamyl peptidases process glutathione conjugates in the biosynthesis of glucosinolates and camalexin in Arabidopsis.
Journal
Sequence
Other DBs