A0A8C2PIQ2 · A0A8C2PIQ2_CAPHI
- ProteinBeta-hexosaminidase
- GeneHEXA
- StatusUniProtKB unreviewed (TrEMBL)
- Organism
- Amino acids546 (go to sequence)
- Protein existenceInferred from homology
- Annotation score4/5
Function
function
Hydrolyzes the non-reducing end N-acetyl-D-hexosamine and/or sulfated N-acetyl-D-hexosamine of glycoconjugates, such as the oligosaccharide moieties from proteins and neutral glycolipids, or from certain mucopolysaccharides. The isozyme S is as active as the isozyme A on the anionic bis-sulfated glycans, the chondroitin-6-sulfate trisaccharide (C6S-3), and the dermatan sulfate pentasaccharide, and the sulfated glycosphingolipid SM2. The isozyme B does not hydrolyze each of these substrates, however hydrolyzes efficiently neutral oligosaccharide. Only the isozyme A is responsible for the degradation of GM2 gangliosides in the presence of GM2A.
Catalytic activity
- N-acetyl-beta-D-6-sulfogalactosaminyl-(1->4)-alpha-L-iduronyl-(1->3)-N-acetyl-D-6-sulfogalactosamine + H2O = alpha-L-iduronyl-(1->3)-N-acetyl-D-6-sulfogalactosamine + N-acetyl-D-6-sulfogalactosamineThis reaction proceeds in the forward direction.
- N-acetyl-beta-D-galactosaminyl-(1->4)-beta-D-3-sulfogalactosyl-(1->4)-beta-D-glucosyl-(1<->1')-ceramide + H2O = a beta-D-3-sulfogalactosyl-(1->4)-beta-D-glucosyl-(1<->1')-ceramide + N-acetyl-beta-D-galactosamineThis reaction proceeds in the forward direction.
- a ganglioside GM2 (d18:1(4E)) + H2O = a ganglioside GM3 (d18:1(4E)) + N-acetyl-beta-D-galactosamineThis reaction proceeds in the forward direction.
- a ganglioside GM2 + H2O = a ganglioside GM3 + N-acetyl-beta-D-galactosamineThis reaction proceeds in the forward direction.
- beta-D-GalNAc-(1->4)-alpha-L-IdoA-(1->3)-beta-D-GalNAc-4-sulfate-(1->4)-alpha-L-IdoA-(1->3)-D-GalNAc-4-sulfate + H2O = alpha-L-IdoA-(1->3)-beta-D-GalNAc-4-sulfate-(1->4)-alpha-L-IdoA-(1->3)-D-GalNAc-4-sulfate + N-acetyl-D-galactosamineThis reaction proceeds in the forward direction.
Features
Showing features for active site.
Type | ID | Position(s) | Description | ||
---|---|---|---|---|---|
Active site | 323 | Proton donor | |||
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | lysosome | |
Cellular Component | membrane | |
Molecular Function | beta-N-acetylhexosaminidase activity | |
Biological Process | carbohydrate metabolic process | |
Biological Process | ganglioside catabolic process | |
Biological Process | glycosaminoglycan metabolic process |
Keywords
- Molecular function
- Biological process
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameBeta-hexosaminidase
- EC number
Gene names
Organism names
- Organism
- Taxonomic lineageEukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Laurasiatheria > Artiodactyla > Ruminantia > Pecora > Bovidae > Caprinae > Capra
Accessions
- Primary accessionA0A8C2PIQ2
Proteomes
Subcellular Location
PTM/Processing
Features
Showing features for signal, chain, disulfide bond.
Type | ID | Position(s) | Description | ||
---|---|---|---|---|---|
Signal | 1-22 | ||||
Chain | PRO_5034698327 | 23-546 | Beta-hexosaminidase | ||
Disulfide bond | 58↔104 | ||||
Disulfide bond | 277↔328 | ||||
Disulfide bond | 522↔539 | ||||
Keywords
- PTM
Interaction
Subunit
There are 3 beta-hexosaminidase isozymes: isozyme A (hexosaminidase A) is a heterodimer composed of one subunit alpha and one subunit beta (chain A and B); isozyme B (hexosaminidase B) is a homodimer of two beta subunits (two chains A and B); isozyme S (hexosaminidase S) is a homodimer of two alpha subunits. The composition of the dimer (isozyme A versus isozyme S) has a significant effect on the substrate specificity of the alpha subunit active site.
Structure
Family & Domains
Features
Showing features for domain.
Type | ID | Position(s) | Description | ||
---|---|---|---|---|---|
Domain | 23-145 | Beta-hexosaminidase eukaryotic type N-terminal | |||
Domain | 167-504 | Glycoside hydrolase family 20 catalytic | |||
Sequence similarities
Belongs to the glycosyl hydrolase 20 family.
Keywords
- Domain
Family and domain databases
Sequence
- Sequence statusComplete
- Length546
- Mass (Da)62,026
- Last updated2022-01-19 v1
- Checksum3DC223081C11B8D3