Annotations: 3D3A

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	KOG0496	e3d3aA1	A: beta sandwiches	X: jelly-roll	H: Concanavalin A-like	T: Galactose-binding domain-like	F: KOG0496	ECOD (1.6)
A	BetaGal_dom4_5_2	e3d3aA2	A: beta sandwiches	X: jelly-roll	H: Concanavalin A-like	T: Galactose-binding domain-like	F: BetaGal_dom4_5_2	ECOD (1.6)
A	Glyco_hydro_42	e3d3aA3	A: a/b barrels	X: TIM beta/alpha-barrel	H: TIM barrels (From Topology)	T: TIM barrels	F: Glyco_hydro_42	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	3.20.20.80	Alpha Beta	Alpha-Beta Barrel	TIM Barrel	Glycosidases	CATH (4.3.0)
A	2.60.120.260	Mainly Beta	Sandwich	Jelly Rolls	Galactose-binding domain-like	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF21317	Beta-galactosidase, first all-beta domain (BetaGal_ABD_1)	Beta-galactosidase, first all-beta domain	Beta-galactosidases belong to glycosyl hydrolase 35 family (GH35) which catalyse the cleaveage of beta-linked terminal galactosyl residues from gangliosides, glycoproteins, and glycosaminoglycans. These proteins consist of a catalytic TIM-barrel and ...	Beta-galactosidases belong to glycosyl hydrolase 35 family (GH35) which catalyse the cleaveage of beta-linked terminal galactosyl residues from gangliosides, glycoproteins, and glycosaminoglycans. These proteins consist of a catalytic TIM-barrel and two all-beta domains (ABD1 and ABD2) [1-5]. This entry represents the first all-beta domain ABD1. ABD2 is represented in Pfam:PF13364.	Domain
A	PF01301	Glycosyl hydrolases family 35 (Glyco_hydro_35)	Glycosyl hydrolases family 35	-	Domain
A	PF21467	Beta-galactosidase, galactose-binding domain (BetaGal_gal-bd)	Beta-galactosidase, galactose-binding domain	Beta-galactosidase belongs to Glycoside hydrolase family 35 [1-5]. This entry represents the galactose-binding domain.	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	Beta-galactosidase	hydrolase activity, acting on glycosyl bonds beta-galactosidase activity hydrolase activity, hydrolyzing O-glycosyl compounds hydrolase activity catalytic activity galactosidase activity cation binding ion binding binding metal ion binding small molecule binding	carbohydrate metabolic process primary metabolic process metabolic process	membrane-bounded organelle intracellular organelle intracellular anatomical structure organelle vacuole cytoplasm cellular anatomical entity intracellular membrane-bounded organelle

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR048913	Beta-galactosidase, galactose-binding domain	Domain
A	IPR000421	Coagulation factor 5/8, C-terminal domain	Domain
A	IPR001944	Glycoside hydrolase, family 35	Family
A	IPR031330	Glycoside hydrolase 35, catalytic domain	Domain
A	IPR017853	Glycoside hydrolase superfamily	Homologous Superfamily
A	IPR048912	Beta-galactosidase 1-like , first all-beta domain	Domain
A	IPR008979	Galactose-binding-like domain superfamily	Homologous Superfamily

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.