Large scale preparation of PA-oligosaccharides from glycoproteins using an improved extraction method

We have developed a new method for the large scale preparation of pyridylaminated (PA-) oligosaccharides from glycoproteins. Phenol/chloroform extraction was adapted for the removal of protein and excess 2-aminopyridine, improving the efficiency of preparation. From a 2.5 g sample of human apo-transferrin, 25-30 mu mol of agalacto biantennary PA-oligosaccharide could be obtained. By increasing the concentration of PA-oligosaccharide substrate, we were able to detect a very low level of N-acetylglucosaminlytransferase IV activity in CHO cell extracts.