Structure of PDB 1zga Chain A

Receptor sequence

>1zgaA (length=357) Species: 3880 (Medicago truncatula)

SEESELYHAQIHLYKHVYNFVSSMALKSAMELGIADAIHNHGKPMTLSEL
ASSLKLHPSKVNILHRFLRLLTHNGFFAKTIVKGKEGDEEEEIAYSLTPP
SKLLISGKPTCLSSIVKGALHPSSLDMWSSSKKWFNEDKEQTLFECATGE
SFWDFLNKDSESSTLSMFQDAMASDSRMFKLVLQENKRVFEGLESLVDVG
GGTGGVTKLIHEIFPHLKCTVFDQPQVVGNLTGNENLNFVGGDMFKSIPS
ADAVLLKWVLHDWNDEQSLKILKNSKEAISHKGKDGKVIIIDISIDETSD
DRGLTELQLDYDLVMLTMFLGKERTKQEWEKLIYDAGFSSYKITPISGFK
SLIEVYP

3D structure

• PDB: 1zga Structural basis for dual functionality of isoflavonoid O-methyltransferases in the evolution of plant defense responses.
• Chain: A
• Resolution: 2.35 Å

Enzymatic activity

• Catalytic site (original residue number in PDB): H268 D269 D299 E330
• Catalytic site (residue number reindexed from 1): H261 D262 D292 E323
• Enzyme Commision number: 2.1.1.212: 2,7,4'-trihydroxyisoflavanone 4'-O-methyltransferase.
  2.1.1.46: isoflavone 4'-O-methyltransferase.

Interaction with ligand

Site #	Ligand	Ligand chain	Binding residues on receptor (original residue number in PDB)	Binding residues on receptor (residue number reindexed from 1)	Binding affinity
BS01	HMK	A	G125 S131 F159 M174 F175 D182 M322	G118 S124 F152 M167 F168 D175 M315
BS02	SAH	A	G207 V213 D230 Q231 D250 M251 K264 W265	G200 V206 D223 Q224 D243 M244 K257 W258

Gene Ontology

Molecular Function

• GO:0008168 methyltransferase activity
• GO:0008171 O-methyltransferase activity
• GO:0008757 S-adenosylmethionine-dependent methyltransferase activity
• GO:0030746 isoflavone 4'-O-methyltransferase activity
• GO:0046983 protein dimerization activity
• GO:0102670 2,7,4'-trihydroxyisoflavanone-4'-O-methyltransferase activity

Biological Process

• GO:0032259 methylation

External links

• PDB: RCSB:1zga, PDBe:1zga, PDBj:1zga
• PDBsum: 1zga
• PubMed: 17172354
• UniProt: Q29U70|I4OMT_MEDTR Isoflavone 4'-O-methyltransferase (Gene Name=HI4'OMT)