Glycoproteins of Bovine Pancreatic Juice

作者：Thomas H. Plummer, Penelope A. Kosinski · 发表于：Journal of Biological Chemistry · 年份：1968 · DOI：10.1016/s0021-9258(18)94514-x · 被引用次数：69 · 研究领域：Enzyme Production and Characterization、Microbial Metabolites in Food Biotechnology、Enzyme Catalysis and Immobilization

Abstract Chromatography on carboxymethyl cellulose and Amberlite IRC-50 was utilized to isolate minor ribonuclease components from bovine pancreatic juice. Two of these components, ribonucleases C and D, were obtained in homogeneous form at yields of 0.48 mg and 0.37 mg, respectively, per g of pooled pancreatic protein, and were detected in three of the four animals examined. Ribonucleases C and D possess amino acid compositions, specific activities, and ultraviolet spectra identical with those of ribonucleases A and B. Analyses for amino sugars indicate 4 residues of glucosamine and 2 residues of N-acetylneuraminic acid bound per molecule of ribonuclease C, and 4 residues of each amino sugar bound per molecule of ribonuclease D. Each glycoprotein also contains mannose, fucose, and galactose. Peptide maps of tryptic digests of reduced, cyanoethylated ribonucleases C and D are identical with those from ribonuclease B and reveal that the carbohydrate is attached to peptide tryptic-11.