1QBA

BACTERIAL CHITOBIASE, GLYCOSYL HYDROLASE FAMILY 20

External Resource: Annotation

Domain Annotation: SCOP/SCOPe Classification
Domain Annotation: SCOP2 Classification
Domain Annotation: ECOD Classification
Domain Annotation: CATH
Protein Family Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification
Structure Motif: Primary M-CSA Annotation

Domain Annotation: SCOP/SCOPe Classification SCOP-e Database Homepage

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
A	d1qbaa1	All beta proteins	Immunoglobulin-like beta-sandwich	E set domains	E-set domains of sugar-utilizing enzymes	Bacterial chitobiase (N-acetyl-beta-glucoseaminidase), C-terminal domain	(Serratia marcescens ) [TaxId: 615 ],	SCOPe (2.08)
A	d1qbaa2	All beta proteins	Common fold of diphtheria toxin/transcription factors/cytochrome f	Carbohydrate-binding domain	Bacterial chitobiase, n-terminal domain	Bacterial chitobiase, n-terminal domain	(Serratia marcescens ) [TaxId: 615 ],	SCOPe (2.08)
A	d1qbaa3	Alpha and beta proteins (a/b)	TIM beta/alpha-barrel	(Trans)glycosidases	beta-N-acetylhexosaminidase catalytic domain	Bacterial chitobiase (beta-N-acetylhexosaminidase)	(Serratia marcescens ) [TaxId: 615 ],	SCOPe (2.08)
A	d1qbaa4	Alpha and beta proteins (a+b)	Zincin-like	beta-N-acetylhexosaminidase-like domain	beta-N-acetylhexosaminidase domain	Bacterial chitobiase, Domain 2	(Serratia marcescens ) [TaxId: 615 ],	SCOPe (2.08)

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A	SCOP2 Family	beta-N-acetylhexosaminidase domain	8023180	4001646	SCOP2 (2022-06-29)
A	SCOP2 Family	bacterial chitobiase, n-terminal domain	8027812	4002038	SCOP2 (2022-06-29)
A	SCOP2 Family	beta-N-acetylhexosaminidase catalytic domain	8031014	4003199	SCOP2 (2022-06-29)
A	SCOP2 Family	E-set domains of sugar-utilizing enzymes	8054902	4007565	SCOP2 (2022-06-29)
A	SCOP2 Superfamily	beta-N-acetylhexosaminidase-like domain	8035560	3000192	SCOP2 (2022-06-29)
A	SCOP2 Superfamily	Carbohydrate-binding domain	8040191	3000706	SCOP2 (2022-06-29)
A	SCOP2 Superfamily	(Trans)glycosidases	8043392	3000313	SCOP2 (2022-06-29)
A	SCOP2 Superfamily	E set domains	8054903	3000070	SCOP2 (2022-06-29)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	CHB_HEX_C	e1qbaA1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: CHB_HEX_C	ECOD (1.6)
A	CHB_HEX	e1qbaA2	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Common fold of diphtheria toxin/transcription factors/cytochrome f	F: CHB_HEX	ECOD (1.6)
A	Glyco_hydro_20	e1qbaA3	A: a/b barrels	X: TIM beta/alpha-barrel	H: TIM barrels (From Topology)	T: TIM barrels	F: Glyco_hydro_20	ECOD (1.6)
A	Glyco_hydro_20b	e1qbaA4	A: mixed a+b and a/b	X: Zincin-like	H: beta-N-acetylhexosaminidase-like domain (From Topology)	T: beta-N-acetylhexosaminidase-like domain	F: Glyco_hydro_20b	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	2.60.40.290	Mainly Beta	Sandwich	Immunoglobulin-like		CATH (4.3.0)
A	3.30.379.10	Alpha Beta	2-Layer Sandwich	Chitobiase	domain 2	CATH (4.3.0)
A	3.20.20.80	Alpha Beta	Alpha-Beta Barrel	TIM Barrel	Glycosidases	CATH (4.3.0)
A	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF02838	Glycosyl hydrolase family 20, domain 2 (Glyco_hydro_20b)	Glycosyl hydrolase family 20, domain 2	This domain has a zincin-like fold.	Domain
A	PF03173	Putative carbohydrate binding domain (CHB_HEX)	Putative carbohydrate binding domain	This domain represents the N terminal domain in chitobiases and beta-hexosaminidases EC:3.2.1.52. It is composed of a beta sandwich structure that is similar in structure to the cellulose binding domain of cellulase from Cellulomonas fimi [1]. This ...	This domain represents the N terminal domain in chitobiases and beta-hexosaminidases EC:3.2.1.52. It is composed of a beta sandwich structure that is similar in structure to the cellulose binding domain of cellulase from Cellulomonas fimi [1]. This suggests that this may be a carbohydrate binding domain.	Domain
A	PF03174	Chitobiase/beta-hexosaminidase C-terminal domain (CHB_HEX_C)	Chitobiase/beta-hexosaminidase C-terminal domain	This short domain represents the C terminal domain in chitobiases and beta-hexosaminidases EC:3.2.1.52. It is composed of a beta sandwich structure [1]. The function of this domain is unknown.	Domain
A	PF00728	Glycosyl hydrolase family 20, catalytic domain (Glyco_hydro_20)	Glycosyl hydrolase family 20, catalytic domain	This domain has a TIM barrel fold.	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	CHITOBIASE	hydrolase activity, acting on glycosyl bonds hexosaminidase activity beta-N-acetylhexosaminidase activity beta-N-acetylglucosaminidase activity hydrolase activity, hydrolyzing O-glycosyl compounds hydrolase activity catalytic activity binding polysaccharide binding carbohydrate binding	carbohydrate derivative catabolic process catabolic process carbohydrate derivative metabolic process chitin metabolic process aminoglycan catabolic process macromolecule catabolic process glucosamine-containing compound catabolic process amino sugar catabolic process aminoglycan metabolic process amino sugar metabolic process metabolic process cellular process macromolecule metabolic process chitin catabolic process carbohydrate derivative catabolic process catabolic process carbohydrate derivative metabolic process chitin metabolic process aminoglycan catabolic process macromolecule catabolic process glucosamine-containing compound catabolic process amino sugar catabolic process aminoglycan metabolic process amino sugar metabolic process metabolic process cellular process macromolecule metabolic process chitin catabolic process glucosamine-containing compound metabolic process glycosaminoglycan metabolic process carbohydrate metabolic process polysaccharide metabolic process polysaccharide catabolic process carbohydrate catabolic process primary metabolic process	cellular anatomical structure membrane periplasmic space

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR012291	CBM2, carbohydrate-binding domain superfamily	Homologous Superfamily
A	IPR004866	Chitobiase/beta-hexosaminidases, N-terminal domain	Domain
A	IPR017853	Glycoside hydrolase superfamily	Homologous Superfamily
A	IPR029018	Beta-hexosaminidase-like, domain 2	Homologous Superfamily
A	IPR015883	Glycoside hydrolase family 20, catalytic domain	Domain
A	IPR008965	CBM2/CBM3, carbohydrate-binding domain superfamily	Homologous Superfamily
A	IPR004867	Chitobiase C-terminal domain	Domain
A	IPR013783	Immunoglobulin-like fold	Homologous Superfamily
A	IPR014756	Immunoglobulin E-set	Homologous Superfamily
A	IPR025705	Beta-hexosaminidase	Family
A	IPR015882	Beta-hexosaminidase, bacterial type, N-terminal	Domain

Structure Motif Annotation: Mechanism and Catalytic Site Atlas M-CSA Database Homepage

Chains	Enzyme Name	Description	Catalytic Residues
A	beta-N-acetylhexosaminidase M-CSA #899	Chitin, the second most abundant polysaccharide on earth, is degraded by chitinases and chitobiases. This entry represents the glycosidase family 20 chitobiase which digests the beta-1,4-glycosidic bonds in N-acetylglucosamine (GlcNAc) oligomers (mainly dimers). It has a retaining mechanism. Human beta-hexosaminidase A	Defined by 2 residues: ASP:A-512 [auth A-539]GLU:A-513 [auth A-540] \| Explore in 3D: M-CSA Motif Definition Search M-CSA Motif EC: 3.2.1.52 (PDB Primary Data) Search M-CSA Motif + EC 3.2.1.52

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.