Structural study of the carbohydrate moiety of bovine pancreatic ribonuclease B.

The sugar chain of bovine pancreatic ribonuclease B was released from the polypeptide moiety by hydrazinolysis and by endo-beta-N-acetylglucosaminidase H digestion, and reduced with NaB[3H]4 after N-acetylation. The radioactive oligosaccharide mixtures thus obtained were fractionated by Bio-Gel P-4 column chromatography, and their structures were studied by sequential exoglycosidase digestion, methylation study, periodate oxidation and acetolysis. The results show that bovine pancreatic ribonuclease B has one of the following sugar chains as asparagine-linked carbohydrate. Formula (See Text).