Thus, the two substrates of this enzyme are UDP-N-acetyl-D-galactosamine and polypeptide, whereas its two products are UDP and N-acetyl-D-galactosaminyl-polypeptide.

This enzyme belongs to the family of glycosyltransferases, specifically the hexosyltransferases. This enzyme participates in o-glycan biosynthesis and glycan structures - biosynthesis 1. It has 2 cofactors: manganese, and calcium.

Nomenclature

The systematic name of this enzyme class is UDP-N-acetyl-D-galactosamine:polypeptide N-acetylgalactosaminyl-transferase. Other names in common use include:

protein-UDP acetylgalactosaminyltransferase,
UDP-GalNAc:polypeptide N-acetylgalactosaminyl transferase,
UDP-N-acetylgalactosamine:kappa-casein polypeptide,
N-acetylgalactosaminyltransferase,
uridine diphosphoacetylgalactosamine-glycoprotein,
acetylgalactosaminyltransferase,
glycoprotein acetylgalactosaminyltransferase,
polypeptide-N-acetylgalactosamine transferase,
UDP-acetylgalactosamine-glycoprotein,
acetylgalactosaminyltransferase,
UDP-acetylgalactosamine:peptide-N-galactosaminyltransferase,
UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase,
UDP-N-acetyl-alpha-D-galactosamine:polypeptide,
N-acetylgalactosaminyltransferase,
UDP-N-acetylgalactosamine-glycoprotein,
N-acetylgalactosaminyltransferase,
UDP-N-acetylgalactosamine-protein N-acetylgalactosaminyltransferase,
UDP-N-acetylgalactosamine:polypeptide,
N-acetylgalactosaminyltransferase, and
UDP-N-acetylgalactosamine:protein N-acetylgalactosaminyl transferase.

References

Sugiura M, Kawasaki T, Yamashina I (1982). "Purification and characterization of UDP-GalNAc:polypeptide N-acetylgalactosamine transferase from an ascites hepatoma, AH 66". J. Biol. Chem. 257 (16): 9501–7. PMID 6809738.
Takeuchi M, Yoshikawa M, Sasaki R, Chiba H (1985). "Purification and characterization of UDP-N-acetylgalactosamine-kappa-casein polypeptide N-acetylgalactosaminyltransferase from mammary-gland of lactating cow". Agric. Biol. Chem. 49 (4): 1059–1069. doi:10.1271/bbb1961.49.1059.

Transferases: glycosyltransferases (EC 2.4)

2.4.1: Hexosyl-
transferases

Glucosyl-	Phosphorylase Starch Glycogen Cellobiose Myo- Glycogen synthase Debranching enzyme Branching enzyme 1,3-Beta-glucan synthase Ceramide glucosyltransferase N-glycosyltransferase
Galactosyl-	Lactose synthase B-N-acetylglucosaminyl-glycopeptide b-1,4-galactosyltransferase Glycoprotein-N-acetylgalactosamine 3-beta-galactosyltransferase (C1GALT1)
Glucuronosyl-	B3GAT1 B3GAT2 B3GAT3 UGT1A1 UGT1A3 UGT1A4 UGT1A5 UGT1A6 UGT1A7 UGT1A8 UGT1A9 UGT1A10 UGT2A1 UGT2A2 UGT2A3 UGT2B4 UGT2B7 UGT2B10 UGT2B11 UGT2B15 UGT2B17 UGT2B28 Hyaluronan synthase: HAS1 HAS2 HAS3
Fucosyl-	POFUT1 POFUT2 FUT1 FUT2 FUT3 FUT4 FUT5 FUT6 FUT7 FUT8 FUT9 FUT10 FUT11
Mannosyl-	Dolichyl-phosphate-mannose-protein mannosyltransferase POMT1 POMT2 DPM1 DPM3 ALG1 ALG2 ALG3 ALG6 ALG8 ALG9 ALG12

2.4.2: Pentosyl-
transferases

Ribose

ADP-ribosyltransferase	NAD⁺:diphthamide ADP-ribosyltransferase Diphtheria toxin Pseudomonas exotoxin NAD(P)⁺:arginine ADP-ribosyltransferase Pertussis toxin Cholera toxin Poly ADP ribose polymerase Sirtuin
Phosphoribosyltransferase	Adenine phosphoribosyltransferase Hypoxanthine-guanine phosphoribosyltransferase Uracil phosphoribosyltransferase Amidophosphoribosyltransferase
Other	Purine nucleoside phosphorylase: Thymidine phosphorylase ECGF1

Other

2.4.99: Sialyl
transferases

v t e Enzymes
Activity	Active site Binding site Catalytic triad Oxyanion hole Enzyme promiscuity Diffusion-limited enzyme Cofactor Enzyme catalysis
Regulation	Allosteric regulation Cooperativity Enzyme inhibitor Enzyme activator
Classification	EC number Enzyme superfamily Enzyme family List of enzymes
Kinetics	Enzyme kinetics Eadie–Hofstee diagram Hanes–Woolf plot Lineweaver–Burk plot Michaelis–Menten kinetics
Types	EC1 Oxidoreductases (list) EC2 Transferases (list) EC3 Hydrolases (list) EC4 Lyases (list) EC5 Isomerases (list) EC6 Ligases (list) EC7 Translocases (list)