Annotations: 3EZX

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	B12-binding_2	e3ezxA4	A: alpha arrays	X: Methionine synthase domain-like (From Topology)	H: Methionine synthase domain-like (From Topology)	T: Methionine synthase domain-like	F: B12-binding_2	ECOD (1.6)
A	B12-binding	e3ezxA2	A: a/b three-layered sandwiches	X: Flavodoxin-like	H: Class I glutamine amidotransferase-like	T: CheY-like	F: B12-binding	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	1.10.1240.10	Mainly Alpha	Orthogonal Bundle	Methyltransferase, Methionine Synthase (B12-binding Domains)	Chain A, domain 1	CATH (4.3.0)
A	3.40.50.280	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold	Cobalamin-binding domain	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF02607	B12 binding domain (B12-binding_2)	B12 binding domain	This B12 binding domain is found in methionine synthase EC:2.1.1.13 Swiss:Q99707, and other shorter proteins that bind to B12. This domain is always found to the N-terminus of Pfam:PF02310. The structure of this domain is known [1], it is a 4 helix ...	This B12 binding domain is found in methionine synthase EC:2.1.1.13 Swiss:Q99707, and other shorter proteins that bind to B12. This domain is always found to the N-terminus of Pfam:PF02310. The structure of this domain is known [1], it is a 4 helix bundle. Many of the conserved residues in this domain are involved in B12 binding, such as those in the MXXVG motif.	Domain
A	PF02310	B12 binding domain (B12-binding)	B12 binding domain	This domain binds to B12 (adenosylcobamide)[1-3], it is found in several enzymes, such as glutamate mutase Swiss:Q05488, methionine synthase Swiss:Q99707 and methylmalonyl-CoA mutase Swiss:P22033. It contains a conserved DxHxxGx(41)SxVx(26)GG motif, ...	This domain binds to B12 (adenosylcobamide)[1-3], it is found in several enzymes, such as glutamate mutase Swiss:Q05488, methionine synthase Swiss:Q99707 and methylmalonyl-CoA mutase Swiss:P22033. It contains a conserved DxHxxGx(41)SxVx(26)GG motif, which is important for B12 binding [2].	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	Monomethylamine corrinoid protein 1	cation binding transition metal ion binding ion binding binding metal ion binding cobalt ion binding small molecule binding transferase activity, transferring one-carbon groups monomethylamine methyltransferase activity transferase activity methyltransferase activity catalytic activity vitamin binding cobalamin binding cation binding transition metal ion binding ion binding binding metal ion binding cobalt ion binding small molecule binding transferase activity, transferring one-carbon groups monomethylamine methyltransferase activity transferase activity methyltransferase activity catalytic activity vitamin binding cobalamin binding organic cyclic compound binding tetrapyrrole binding heterocyclic compound binding	cellular respiration energy derivation by oxidation of organic compounds cellular biosynthetic process cellular metabolic process alkane biosynthetic process methane metabolic process generation of precursor metabolites and energy hydrocarbon metabolic process organic substance metabolic process biosynthetic process energy derivation by oxidation of reduced inorganic compounds cellular alkane metabolic process organic substance biosynthetic process methanogenesis cellular respiration energy derivation by oxidation of organic compounds cellular biosynthetic process cellular metabolic process alkane biosynthetic process methane metabolic process generation of precursor metabolites and energy hydrocarbon metabolic process organic substance metabolic process biosynthetic process energy derivation by oxidation of reduced inorganic compounds cellular alkane metabolic process organic substance biosynthetic process methanogenesis metabolic process cellular process hydrocarbon biosynthetic process anaerobic respiration	-

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR003759	Cobalamin (vitamin B12)-binding module, cap domain	Domain
A	IPR036724	Cobalamin-binding domain superfamily	Homologous Superfamily
A	IPR012741	Methyltransferase cognate corrinoid protein	Domain
A	IPR006158	Cobalamin (vitamin B12)-binding domain	Domain
A	IPR036594	Methionine synthase domain	Homologous Superfamily

RCSB PDB Core Operations are funded by the National Science Foundation (DBI-1832184), 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 R01GM133198.