UDP-N-acetyl-D-glucosamine-asparagine sequon N-acetyl-beta-D-glucosaminyl-transferase-activity in human serum

Carbohydr Res. 1976 Jul:49:455-73. doi: 10.1016/s0008-6215(00)83163-8.


Serum contains a sugar transferase which is able to catalyse the glycosylation in vitro of the asparagine residue present in the sequence Asn.Leu.Thr in bovine pancreatic ribonuclease. UDP-2-Acetamido-2-deoxy-D-glucose (UDP-N-acetyl-D-glucosamine) acts as a donor, although the mechanism of the transfer is unexplored. Spermidine and Mn2+, as well as CDP-choline, can act as activators for the reaction. Monoglycosylated ribonuclease (ribonuclease-GlcNAc) has been separated (23% yield) from unreacted ribonuclease A by affinity chromatography on a column of wheat-germ agglutinin bound to Sepharose, and characterised. A possible reason for the presence of the enzyme in serum is suggested.

MeSH terms

  • Acetylglucosamine
  • Amino Acids / analysis
  • Animals
  • Asparagine
  • Cattle
  • Chromatography, Affinity
  • Cytidine Diphosphate Choline / pharmacology
  • Hexosyltransferases / blood*
  • Humans
  • Kinetics
  • Manganese / pharmacology
  • Pancreas / enzymology
  • Polyamines / pharmacology
  • Protein Binding
  • Ribonucleases / isolation & purification
  • Ribonucleases / metabolism*
  • Uridine Diphosphate N-Acetylglucosamine


  • Amino Acids
  • Polyamines
  • Manganese
  • Uridine Diphosphate N-Acetylglucosamine
  • Cytidine Diphosphate Choline
  • Asparagine
  • Hexosyltransferases
  • Ribonucleases
  • Acetylglucosamine