N-acetyllactosaminide 3-alpha-galactosyltransferase
In enzymology, a N-acetyllactosaminide 3-alpha-galactosyltransferase (EC 2.4.1.87) is an enzyme that catalyzes the chemical reaction
- UDP-galactose + beta-D-galactosyl-(1->4)-beta-N-acetyl-D-glucosaminyl-R UDP + alpha-D-galactosyl-(1->3)-beta-D-galactosyl-(1->4)-beta-N- acetylglucosaminyl-R
| N-acetyllactosaminide 3-alpha-galactosyltransferase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC no. | 2.4.1.87 | ||||||||
| CAS no. | 128449-51-4 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
| |||||||||
Thus, the two substrates of this enzyme are UDP-galactose and [[beta-D-galactosyl-(1->4)-beta-N-acetyl-D-glucosaminyl-R]], whereas its 3 products are UDP, [[alpha-D-galactosyl-(1->3)-beta-D-galactosyl-(1->4)-beta-N-]], and acetylglucosaminyl-R.
This enzyme belongs to the family of glycosyltransferases, specifically the hexosyltransferases. The systematic name of this enzyme class is UDP-galactose:N-acetyllactosaminide 3-alpha-D-galactosyltransferase. Other names in common use include alpha-galactosyltransferase, UDP-Gal:beta-D-Gal(1,4)-D-GlcNAc alpha(1,3)-galactosyltransferase, UDP-Gal:N-acetyllactosaminide alpha(1,3)-galactosyltransferase, UDP-Gal:N-acetyllactosaminide alpha-1,3-D-galactosyltransferase, UDP-Gal:Galbeta1->4GlcNAc-R alpha1->3-galactosyltransferase, UDP-galactose-acetyllactosamine alpha-D-galactosyltransferase, UDPgalactose:beta-D-galactosyl-beta-1,4-N-acetyl-D-glucosaminyl-, glycopeptide alpha-1,3-D-galactosyltransferase, glucosaminylglycopeptide alpha-1,3-galactosyltransferase, uridine diphosphogalactose-acetyllactosamine, alpha1->3-galactosyltransferase, uridine diphosphogalactose-acetyllactosamine galactosyltransferase, uridine, diphosphogalactose-, galactosylacetylglucosaminylgalactosylglucosylceramide, galactosyltransferase, beta-D-galactosyl-N-acetylglucosaminylglycopeptide, and alpha-1,3-galactosyltransferase. This enzyme participates in 3 metabolic pathways: glycosphingolipid biosynthesis - lactoseries, glycosphingolipid biosynthesis - neo-lactoseries, and glycan structures - biosynthesis 2.
Structural studies
As of late 2007, 3 structures have been solved for this class of enzymes, with PDB accession codes 2JCF, 2JCK, and 2JCL.
References
- Basu M, Basu S (1973). "Enzymatic synthesis of a blood group B-related pentaglycosylceramide by an alpha-galactosyltransferase from rabbit bone marrow". J. Biol. Chem. 248 (5): 1700–6. PMID 4632915.
- Blanken WM, Van den Eijnden DH (1985). "Biosynthesis of terminal Gal alpha 1--3Gal beta 1--4GlcNAc-R oligosaccharide sequences on glycoconjugates. Purification and acceptor specificity of a UDP-Gal:N-acetyllactosaminide alpha 1--3-galactosyltransferase from calf thymus". J. Biol. Chem. 260 (24): 12927–34. PMID 3932335.
- Blake DA, Goldstein IJ (1981). "An alpha-D-galactosyltransferase activity in Ehrlich ascites tumor cells. Biosynthesis and characterization of a trisaccharide (alpha-D-galactose-(1 goes to 3)-N-acetyllactosamine)". J. Biol. Chem. 256 (11): 5387–93. PMID 6787040.