Globotriaosylceramide 3-beta-N-acetylgalactosaminyltransferase explained

galactosylgalactosylglucosylceramide beta-D-acetylgalactosaminyltransferase
Ec Number:	2.4.1.79
Cas Number:	62213-46-1
Go Code:	0047273
Altnames:	uridine, diphosphoacetylgalactosamine-galactosylgalactosylglucosylceramide, acetylgalactosaminyltransferase, globoside synthetase, UDP-N-acetylgalactosamine:globotriaosylceramide, beta-3-N-acetylgalactosaminyltransferase, galactosylgalactosylglucosylceramide, beta-D-acetylgalactosaminyltransferase, UDP-N-acetylgalactosamine:globotriaosylceramide, beta1,3-N-acetylgalactosaminyltransferase, globoside synthase, galactosylgalactosylglucosylceramide, beta-D-acetylgalactosaminyltransferase, UDP-N-acetyl-D-galactosamine:D-galactosyl-1,4-D-galactosyl-1,4-D-, glucosylceramide beta-N-acetyl-D-galactosaminyltransferase, beta3GalNAc-T1, UDP-N-acetyl-D-galactosamine:alpha-D-galactosyl-(1->4)-beta-D-, galactosyl-(1->4)-beta-D-glucosylceramide, 3III-beta-N-acetyl-D-galactosaminyltransferase, UDP-N-acetyl-D-galactosamine:alpha-D-galactosyl-(1->4)-beta-D-, galactosyl-(1->4)-beta-D-glucosyl-(11)-ceramide, 3III-beta-N-acetyl-D-galactosaminyltransferase

In enzymology, a globotriaosylceramide 3-beta-N-acetylgalactosaminyltransferase is an enzyme that catalyzes the chemical reaction

UDP-N-acetyl-D-galactosamine + alpha-D-galactosyl-(1->4)-beta-D-galactosyl-(1->4)-beta-D-glucosyl- (11)-ceramide

\rightleftharpoons UDP + N-acetyl-beta-D-galactosaminyl-(1->3)-alpha-D-galactosyl-(1->4)- beta-D-galactosyl-(1->4)-beta-D-glucosyl-(11)-ceramide

The 3 substrates of this enzyme are UDP-N-acetyl-D-galactosamine, alpha-D-galactosyl-(1->4)-beta-D-galactosyl-(1->4)-beta-D-glucosyl-, and (11)-ceramide, whereas its 3 products are UDP, N-acetyl-beta-D-galactosaminyl-(1->3)-alpha-D-galactosyl-(1->4)-, and beta-D-galactosyl-(1->4)-beta-D-glucosyl-(11)-ceramide.

Wrongly characterized previously as globotriosylceramide beta-1,6-N-acetylgalactosaminyl-transferase (^[1]

This enzyme belongs to the family of glycosyltransferases, specifically the hexosyltransferases. The systematic name of this enzyme class is UDP-N-acetyl-D-galactosamine:alpha-D-galactosyl-(1->4)-beta-D-galact osyl-(1->4)-beta-D-glucosyl-(11)-ceramide III3-beta-N-acetyl-D-galactosaminyltransferase. This enzyme participates in glycosphingolipid biosynthesis - globoseries and glycan structures - biosynthesis 2.

References

• Chien JL, Williams T, Basu S . 1973 . Biosynthesis of a globoside-type glycosphingolipid by a -N-acetylgalactosaminyltransferase from embryonic chicken brain . J. Biol. Chem. . 248 . 1778 - 85 . 4632917 . 5 .
• Ishibashi T, Kijimoto S, Makita A . 1974 . Biosynthesis of globoside and Forssman hapten from trihexosylceramide and properties of beta-N-acetyl-galactosaminyltransferase of guinea pig kidney . Biochim. Biophys. Acta . 337 . 92 - 106 . 4433547 . 1 . 10.1016/0005-2760(74)90043-5.
• Taniguchi N, Makita A . 1984 . Purification and characterization of UDP-N-acetylgalactosamine: globotriaosylceramide beta-3-N-acetylgalactosaminyltransferase, a synthase of human blood group P antigen, from canine spleen . J. Biol. Chem. . 259 . 5637 - 42 . 6425294 . 9 .
• Urano T, Furukawa K . 2000 . Expression cloning of human globoside synthase cDNAs. Identification of beta 3Gal-T3 as UDP-N-acetylgalactosamine:globotriaosylceramide beta 1,3-N-acetylgalactosaminyltransferase . J. Biol. Chem. . 275 . 40498 - 503 . 10993897 . 10.1074/jbc.M006902200 . 51 . free .

Notes and References

1. Lockney MW, Sweeley CC . Characterization of a glycosphingolipid beta-N-acetylgalactosaminyl-transferase activity in cultured hamster (nil) cells . Biochimica et Biophysica Acta (BBA) - Lipids and Lipid Metabolism . 712 . 2 . 234–41 . August 1982 . 6812637 . 10.1016/0005-2760(82)90339-3 .