Glycosylation of ribonuclease A catalysed by rabbit liver extracts.
Crude extracts of rabbit liver catalyse in vitro the transfer of N-acetylglucosamine from UDP-N-acetylglucosamine to bovine pancreatic ribonuclease A. The enzymic activity is contained in rough endoplasmic reticulum. It has an absolute requirement for a bivalent metal ion: Co-2+ greater than Mn-2+ greater than Ni-2+. Mg-2+ is ineffective. There is enzymic activity in the absence of detergent, but increased activity is observed in the presence of Triton X-100. The site of glycosylation of ribonuclease A is asparagine-34, and glycosylation occurs only at this point. These findings agree with the hypothesis that the sequence Asn-X-Thr(Ser) (where X may be one of a number of types of amino acid) is a necessary, but not sufficient, condition for N-acetylglucosaminylation of a protein-bound asparagine residue.
D000117:Acetylglucosamine / Q000378:metabolism*; D000818:Animals; D001216:Asparagine; D003035:Cobalt; D004721:Endoplasmic Reticulum / Q000201:enzymology; D005944:Glucosamine / Q000031:analogs & derivatives*; D006020:Glycopeptides / Q000302:isolation & purification; D008099:Liver / Q000201:enzymology*; D008345:Manganese; D009532:Nickel; D010455:Peptides / Q000032:analysis; D011092:Polyethylene Glycols; D011817:Rabbits; D012260:Ribonucleases / Q000032:analysis / Q000378:metabolism*
D006020:Glycopeptides; D010455:Peptides; D003035:Cobalt; D011092:Polyethylene Glycols; D008345:Manganese; D001216:Asparagine; D009532:Nickel; D012260:Ribonucleases; D005944:Glucosamine; D000117:Acetylglucosamine