N‐Glycosylation of Yeast Proteins

Abstract
The enzyme transferring the oligosaccharide from DolPP‐(GlcNAc)2(Man)9(Glc)3 to asparagine residues of glycoproteins has been solubilized from yeast membranes by extraction with detergents. Enzyme activity was tested by measuring transfer of the glycosyl moiety from DolPP‐[14C]saccharidcs to the hexapeptide Tyr‐Asn‐Leu‐Thr‐Ser‐Val. The rate of transfer was linear for 20 min, with about 40% of dolichyl‐diphosphate‐bound radioactivity transferred to the peptide. The solubilized enzyme has been characterized as follows: