Names & Taxonomy
- Uniprot ID:
- O94766
- Entry Name:
- B3GA3_HUMAN
- Status:
- reviewed
- Protein Names:
- Galactosylgalactosylxylosylprotein 3-beta-glucuronosyltransferase 3 (EC 2.4.1.135) (Beta-1,3-glucuronyltransferase 3) (Glucuronosyltransferase I) (GlcAT-I) (UDP-GlcUA:Gal beta-1,3-Gal-R glucuronyltransferase) (GlcUAT-I)
- Gene Names:
- B3GAT3
- Gene Names Primary:
- B3GAT3
- Organism:
- Homo sapiens (Human)
Structure
- Length:
- 335
- Sequence:
- MKLKLKNVFLAYFLVSIAGLLYALVQLGQPCDCLPPLRAAAEQLRQKDLRISQLQAELRRPPPAPAQPPEPEALPTIYVVTPTYARLVQKAELVRLSQTLSLVPRLHWLLVEDAEGPTPLVSGLLAASGLLFTHLVVLTPKAQRLREGEPGWVHPRGVEQRNKALDWLRGRGGAVGGEKDPPPPGTQGVVYFADDDNTYSRELFEEMRWTRGVSVWPVGLVGGLRFEGPQVQDGRVVGFHTAWEPSRPFPVDMAGFAVALPLLLDKPNAQFDSTAPRGHLESSLLSHLVDPKDLEPRAANCTRVLVWHTRTEKPKMKQEEQLQRQGRGSDPAIEV
- Proteomes:
- UP000005640
Subcellular location
- Subcellular Location:
- Golgi apparatus membrane
Function
- Function:
- Glycosaminoglycans biosynthesis (PubMed:25893793). Involved in forming the linkage tetrasaccharide present in heparan sulfate and chondroitin sulfate. Transfers a glucuronic acid moiety from the uridine diphosphate-glucuronic acid (UDP-GlcUA) to the common linkage region trisaccharide Gal-beta-1,3-Gal-beta-1,4-Xyl covalently bound to a Ser residue at the glycosaminylglycan attachment site of proteoglycans. Can also play a role in the biosynthesis of l2/HNK-1 carbohydrate epitope on glycoproteins. Shows strict specificity for Gal-beta-1,3-Gal-beta-1,4-Xyl, exhibiting negligible incorporation into other galactoside substrates including Galbeta1-3Gal beta1-O-benzyl, Galbeta1-4GlcNAc and Galbeta1-4Glc. Stimulates 2-phosphoxylose phosphatase activity of PXYLP1 in presence of uridine diphosphate-glucuronic acid (UDP-GlcUA) during completion of linkage region formation (PubMed:24425863).
- Pathway:
- Protein modification; protein glycosylation.
- Catalytic Activity:
- UDP-glucuronate + 3-beta-D-galactosyl-4-beta-D-galactosyl-O-beta-D-xylosylprotein = UDP + 3-beta-D-glucuronosyl-3-beta-D-galactosyl-4-beta-D-galactosyl-O-beta-D-xylosylprotein.
- Cofactor:
- COFACTOR: Name=Mn(2+); Xref=ChEBI:CHEBI:29035;
- Enzyme Regulation:
- ENZYME REGULATION: Inhibited by EDTA.
- Active Site:
- ACT_SITE 281 281 Proton donor/acceptor.
- Gene Ontology Go:
- cis-Golgi network
extracellular exosome
Golgi apparatus
Golgi membrane
integral component of membrane
membrane
galactosylgalactosylxylosylprotein 3-beta-glucuronosyltransferase activity
glucuronosyltransferase activity
metal ion binding
protein phosphatase activator activity
carbohydrate metabolic process
chondroitin sulfate metabolic process
chondroitin sulfate proteoglycan biosynthetic process
dermatan sulfate proteoglycan biosynthetic process
glycosaminoglycan biosynthetic process
glycosaminoglycan metabolic process
heparan sulfate proteoglycan biosynthetic process
positive regulation of catalytic activity
positive regulation of intracellular protein transport
protein glycosylation
small molecule metabolic process - Gene Ontology Biological Process:
- carbohydrate metabolic process
chondroitin sulfate metabolic process
chondroitin sulfate proteoglycan biosynthetic process
dermatan sulfate proteoglycan biosynthetic process
glycosaminoglycan biosynthetic process
glycosaminoglycan metabolic process
heparan sulfate proteoglycan biosynthetic process
positive regulation of catalytic activity
positive regulation of intracellular protein transport
protein glycosylation
small molecule metabolic process - Gene Ontology Molecular Function:
- galactosylgalactosylxylosylprotein 3-beta-glucuronosyltransferase activity
glucuronosyltransferase activity
metal ion binding
protein phosphatase activator activity - Gene Ontology Cellular Component:
- cis-Golgi network
extracellular exosome
Golgi apparatus
Golgi membrane
integral component of membrane
membrane - Keywords:
- 3D-structure
Alternative splicing
Complete proteome
Disease mutation
Disulfide bond
Glycoprotein
Golgi apparatus
Manganese
Membrane
Metal-binding
Reference proteome
Signal-anchor
Transferase
Transmembrane
Transmembrane helix