_EC 2.1.1.46 Isoflavone 4'-O-methyltransferase. 4 PDB entries  
EC 2.-.-.- Transferases. [18,993 PDB entries]
EC 2.1.-.- Transferring one-carbon groups. [1,776 PDB entries]
EC 2.1.1.- Methyltransferases. [1,436 PDB entries]
EC 2.1.1.46 Isoflavone 4'-O-methyltransferase. [4 PDB entries]    
1zg3

Pathway: Biochanin A Biosynthesis
Reaction: S-adenosyl-L-methionine + a 4'-hydroxyisoflavone = S-adenosyl-L- homocysteine + a 4'-methoxyisoflavone.
 


S-adenosyl-L-methionine
+ 4'-hydroxyisoflavone
=
S-adenosyl-L- homocysteine
+ 4'-methoxyisoflavone
Molecule diagrams generated from .mol files obtained from the KEGG ftp site.

Cofactor(s): Mg(2+).
Comments: The enzyme catalyzes the methylation of daidzein and genistein. It does not methylate naringenin, apigenin, luteolin or kaempferol.
Links:   [IntEnz]   [ExPASy]   [KEGG]  

There are 4 PDB entries in enzyme class E.C.2.1.1.46

  PDB code Protein
1zg3
Crystal structure of the isoflavanone 4'-o-methyltransferase with sah and 2,7,4'-trihydroxyisoflavanone
Source: Medicago truncatula. Barrel medic. Organism_taxid: 3880. Gene: omt. Expressed in: escherichia coli bl21. Expression_system_taxid: 511693.
Chain: A (358 residues) CATH domains: 1.10.10.10 3.40.50.150
Bound ligand:   Het Group SAH corresponds to enzyme product S-adenosylhomocysteine
1zga
Crystal structure of isoflavanone 4'-o-methyltransferase com with (+)-6a-hydroxymaackiain
Source: Medicago truncatula. Barrel medic. Organism_taxid: 3880. Expressed in: escherichia coli bl21. Expression_system_taxid: 511693.
Chain: A (357 residues) CATH domains: 1.10.10.10 3.40.50.150
Bound ligand:   Het Group SAH corresponds to enzyme product S-adenosylhomocysteine
1zgj
Crystal structure of isoflavanone 4'-o-methyltransferase com with (+)-pisatin
Source: Medicago truncatula. Barrel medic. Organism_taxid: 3880. Expressed in: escherichia coli bl21. Expression_system_taxid: 511693.
Chain: A (354 residues) CATH domains: 1.10.10.10 3.40.50.150
1zhf
Crystal structure of selenomethionine substituted isoflavano methyltransferase
Source: Medicago truncatula. Barrel medic. Organism_taxid: 3880. Expressed in: escherichia coli bl21. Expression_system_taxid: 511693.
Chain: A (357 residues) CATH domains: 1.10.10.10 3.40.50.150
Bound ligand:   Het Group SAH corresponds to enzyme product S-adenosylhomocysteine