B-1,4-mannosyl-glycoprotein 4-b-N-acetylglucosaminyltransferase explained

Beta-1,4-mannosyl-glycoprotein 4-beta-N-acetylglucosaminyltransferase
Ec Number:	2.4.1.144
Cas Number:	83744-93-8

Beta-1,4-mannosyl-glycoprotein 4-beta-N-acetylglucosaminyltransferase (N-acetylglucosaminyltransferase III, N-glycosyl-oligosaccharide-glycoprotein N-acetylglucosaminyltransferase III, uridine diphosphoacetylglucosamine-glycopeptide beta4-acetylglucosaminyltransferase III, beta-1,4-mannosyl-glycoprotein beta-1,4-N-acetylglucosaminyltransferase, GnTIII) is an enzyme with systematic name UDP-N-acetyl-D-glucosamine:beta-D-mannosyl-glycoprotein 4-beta-N-acetyl-D-glucosaminyltransferase.^[1] ^[2] This enzyme catalyses the following chemical reaction

UDP-N-acetyl-D-glucosamine + beta-D-mannosyl-R

\rightleftharpoons

UDP + 4-(N-acetyl-beta-D-glucosaminyl)-beta-D-mannosyl-R

R represents the remainder of the N-linked oligosaccharide in the glycoprotein acceptor.

Notes and References

Narasimhan S . Control of glycoprotein synthesis. UDP-GlcNAc:glycopeptide beta 4-N-acetylglucosaminyltransferase III, an enzyme in hen oviduct which adds GlcNAc in beta 1-4 linkage to the beta-linked mannose of the trimannosyl core of N-glycosyl oligosaccharides . The Journal of Biological Chemistry . 257 . 17 . 10235–42 . September 1982 . 6213618 .
Book: Schachter H, Narasimhan S, Gleeson P, Vella G . Glycosyltransferases involved in elongation of N-glycosidically linked oligosaccharides of the complex or N-acetyllactosamine type . Methods in Enzymology . 98 . 98–134 . 1983 . 6366476 . 10.1016/0076-6879(83)98143-0 .