Glucuronosyl-N-acetylgalactosaminyl-proteoglycan 4-b-N-acetylgalactosaminyltransferase explained

Glucuronosyl-N-acetylgalactosaminyl-proteoglycan 4-beta-N-acetylgalactosaminyltransferase
Ec Number:	2.4.1.175
Cas Number:	96189-40-1

Glucuronosyl-N-acetylgalactosaminyl-proteoglycan 4-beta-N-acetylgalactosaminyltransferase (N-acetylgalactosaminyltransferase II, UDP-N-acetyl-D-galactosamine:D-glucuronyl-N-acetyl-1,3-beta-D-galactosaminylproteoglycan beta-1,4-N-acetylgalactosaminyltransferase, chondroitin synthase, glucuronyl-N-acetylgalactosaminylproteoglycan beta-1,4-N-acetylgalactosaminyltransferase, uridine diphosphoacetylgalactosamine-chondroitin acetylgalactosaminyltransferase II) is an enzyme with systematic name UDP-N-acetyl-D-galactosamine:beta-D-glucuronosyl-(1->3)-N-acetyl-beta-D-galactosaminyl-proteoglycan 4-beta-N-acetylgalactosaminyltransferase.^[1] ^[2] ^[3] ^[4] This enzyme catalyses the following chemical reaction

UDP-N-acetyl-D-galactosamine + beta-D-glucuronosyl-(1->3)-N-acetyl-beta-D-galactosaminyl-proteoglycan

\rightleftharpoons

UDP + N-acetyl-beta-D-galactosaminyl-(1->4)-beta-D-glucuronosyl-(1->3)-N-acetyl-beta-D-galactosaminyl-proteoglycan

This enzyme is involved in the biosynthesis of chondroitin sulfate.

Notes and References

Rohrmann K, Niemann R, Buddecke E . Two N-acetylgalactosaminyltransferase are involved in the biosynthesis of chondroitin sulfate . European Journal of Biochemistry . 148 . 3 . 463–9 . May 1985 . 3922754 . 10.1111/j.1432-1033.1985.tb08862.x . free .
Kitagawa H, Uyama T, Sugahara K . Molecular cloning and expression of a human chondroitin synthase . The Journal of Biological Chemistry . 276 . 42 . 38721–6 . October 2001 . 11514575 . 10.1074/jbc.M106871200 . free .
DeAngelis PL, Padgett-McCue AJ . Identification and molecular cloning of a chondroitin synthase from Pasteurella multocida type F . The Journal of Biological Chemistry . 275 . 31 . 24124–9 . August 2000 . 10818104 . 10.1074/jbc.M003385200 . free .
Ninomiya T, Sugiura N, Tawada A, Sugimoto K, Watanabe H, Kimata K . Molecular cloning and characterization of chondroitin polymerase from Escherichia coli strain K4 . The Journal of Biological Chemistry . 277 . 24 . 21567–75 . June 2002 . 11943778 . 10.1074/jbc.M201719200 . free .