Annotations: 6I6K

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	Dimerisation	e6i6kA1	A: alpha arrays	X: HTH	H: HTH	T: winged	F: Dimerisation	ECOD (1.6)
A	UNK_F_TYPE	e6i6kA2	A: a/b three-layered sandwiches	X: Rossmann-like	H: Rossmann-related	T: S-adenosyl-L-methionine-dependent methyltransferases	F: UNK_F_TYPE	ECOD (1.6)
B	Dimerisation	e6i6kB1	A: alpha arrays	X: HTH	H: HTH	T: winged	F: Dimerisation	ECOD (1.6)
B	UNK_F_TYPE	e6i6kB2	A: a/b three-layered sandwiches	X: Rossmann-like	H: Rossmann-related	T: S-adenosyl-L-methionine-dependent methyltransferases	F: UNK_F_TYPE	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	3.40.50.150	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold	Vaccinia Virus protein VP39	CATH (utative)
B	3.40.50.150	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold	Vaccinia Virus protein VP39	CATH (utative)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A, B	PF08100	O-methyltransferase dimerisation domain (Dimerisation)	O-methyltransferase dimerisation domain	This domain is found at the N-terminus of plant O-methyltransferases involved in phenylpropanoid metabolism, including caffeic acid O-methyltransferase (COMT), isoflavone O-methyltransferase (IOMT), and chalcone O-methyltransferase (ChOMT). It mediat ...	This domain is found at the N-terminus of plant O-methyltransferases involved in phenylpropanoid metabolism, including caffeic acid O-methyltransferase (COMT), isoflavone O-methyltransferase (IOMT), and chalcone O-methyltransferase (ChOMT). It mediates dimerisation of these enzymes, which is critical for their activity [1-4]. The dimerisation domain forms the central core of the homodimer, with the SAM-binding domains located peripherally [1,3,4]. Dimerisation buries ~30% of the total surface area of the dimer [3]. The domain also contributes to forming the back wall of the substrate binding cavity of the partner monomer [2-4]. Structurally, the dimerisation domain consists primarily of alpha-helices [1-4]. Crystal structures reveal the domain is relatively rigid compared to the more mobile SAM-binding domain, which undergoes conformational changes upon substrate binding [4].	Domain
A, B	PF00891	O-methyltransferase domain (Methyltransf_2)	O-methyltransferase domain	This family includes a range of O-methyltransferases. These enzymes utilise S-adenosyl methionine.	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A, B	O-methyltransferase 1	transferase activity, transferring one-carbon groups tetrahydrocolumbamine 2-O-methyltransferase activity transferase activity methyltransferase activity S-adenosylmethionine-dependent methyltransferase activity catalytic activity O-methyltransferase activity (S)-scoulerine 9-O-methyltransferase activity protein binding binding protein dimerization activity	alkaloid biosynthetic process benzyl isoquinoline alkaloid biosynthetic process isoquinoline alkaloid biosynthetic process alkaloid metabolic process isoquinoline alkaloid metabolic process secondary metabolic process benzyl isoquinoline alkaloid metabolic process secondary metabolite biosynthetic process biosynthetic process metabolic process cellular process methylation	-

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A, B	IPR029063	S-adenosyl-L-methionine-dependent methyltransferase superfamily	Homologous Superfamily
A, B	IPR036388	Winged helix-like DNA-binding domain superfamily	Homologous Superfamily
A, B	IPR016461	O-methyltransferase-like	Family
A, B	IPR001077	O-methyltransferase, C-terminal domain	Domain
A, B	IPR036390	Winged helix DNA-binding domain superfamily	Homologous Superfamily
A, B	IPR012967	O-methyltransferase, dimerisation domain	Domain

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM157729.