CATH Classification

Domain Context

CATH Clusters

Superfamily Spore Coat Polysaccharide Biosynthesis Protein SpsA; Chain A
Functional Family Beta-1,4-galactosyltransferase 3,4-related

Enzyme Information

2.4.1.90
N-acetyllactosamine synthase.
based on mapping to UniProt P15291
UDP-alpha-D-galactose + N-acetyl-D-glucosamine = UDP + N-acetyllactosamine.
-!- The reaction is catalyzed by a component of EC 2.4.1.22, which is identical with EC 2.4.1.38, and by an enzyme from the Golgi apparatus of animal tissues. -!- Formerly EC 2.4.1.98.
2.4.1.-
Hexosyltransferases.
based on mapping to UniProt P15291
2.4.1.22
Lactose synthase.
based on mapping to UniProt P15291
UDP-alpha-D-galactose + D-glucose = UDP + lactose.
-!- The enzyme is a complex of 2 proteins A and B. -!- In the absence of the B protein (alpha-lactalbumin) the enzyme catalyzes the transfer of galactose from UDP-galactose to N-acetylglucosamine (cf. EC 2.4.1.90).
2.4.1.38
Beta-N-acetylglucosaminylglycopeptide beta-1,4-galactosyltransferase.
based on mapping to UniProt P15291
UDP-alpha-D-galactose + N-acetyl-beta-D-glucosaminylglycopeptide = UDP + beta-D-galactosyl-(1->4)-N-acetyl-beta-D-glucosaminylglycopeptide.
-!- Terminal N-acetyl-beta-D-glucosaminyl residues in polysaccharides, glycoproteins and glycopeptides can act as acceptor. -!- High activity is shown toward such residues in branched-chain polysaccharides when these are linked by beta-1,6 links to galactose residues; lower activity toward residues linked to galactose by beta- 1,3 links. -!- A component of EC 2.4.1.22.

UniProtKB Entries (1)

P15291
B4GT1_HUMAN
Homo sapiens
Beta-1,4-galactosyltransferase 1

PDB Structure

PDB 2AE7
External Links
Method X-RAY DIFFRACTION
Organism Escherichia
Primary Citation
Oligosaccharide Preferences of beta1,4-Galactosyltransferase-I: Crystal Structures of Met340His Mutant of Human beta1,4-Galactosyltransferase-I with a Pentasaccharide and Trisaccharides of the N-Glycan Moiety
Ramasamy, V., Ramakrishnan, B., Boeggeman, E., Ratner, D.M., Seeberger, P.H., Qasba, P.K.
J.Mol.Biol.