IUBMB Enzyme Nomenclature


Accepted name: glucuronylgalactosylproteoglycan 4-β-N-acetylgalactosaminyltransferase

Reaction: UDP-N-acetyl-D-galactosamine + β-D-glucuronyl-(1→3)-D-galactosyl-proteoglycan = UDP + N-acetyl-D-galactosaminyl-(1→4)-β-D-glucuronyl-(1→3)-β-D-galactosylproteoglycan

For diagram click here.

Other name(s): N-acetylgalactosaminyltransferase I; glucuronylgalactosylproteoglycan β-1,4-N-acetylgalactosaminyltransferase; uridine diphosphoacetylgalactosamine-chondroitin acetylgalactosaminyltransferase I

Systematic name: UDP-N-acetyl-D-galactosamine:D-glucuronyl-1,3-β-D-galactosyl-proteoglycan β-1,4-N-acetylgalactosaminyltransferase

Comments: Requires Mn2+. Involved in the biosynthesis of chondroitin sulfate. Key enzyme activity for the initiation of chondroitin and dermatan sulfates, transferring GalNAc to the GlcA-Gal-Gal-Xyl-Ser core.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 96189-39-8


1. Rohrmann, K., Niemann, R. and Buddecke, E. Two N-acetylgalactosaminyltransferases are involved in the biosynthesis of chondroitin sulfate. Eur. J. Biochem. 148 (1985) 463-469. [PMID: 3922754]

2. Uyama, T., Kitagawa, H., Tamura, Ji J. and Sugahara, K. Molecular cloning and expression of human chondroitin N-acetylgalactosaminyltransferase: the key enzyme for chain initiation and elongation of chondroitin/dermatan sulfate on the protein linkage region tetrasaccharide shared by heparin/heparan sulfate. J. Biol. Chem. 277 (2002) 8841-8846. [PMID: 11788602]

[EC created 1989, modified 2002]

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