Mild alkaline borohydride treatment of glycoproteins—A method for liberating both N- and O-linked carbohydrate chains

✍ Scribed by Shun-Ichiro Ogata; Kenneth O. Lloyd

• Book ID: 102985899
• Publisher: Elsevier Science
• Year: 1982
• Tongue: English
• Weight: 691 KB
• Volume: 119
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(82)90597-8

✦ Synopsis

N-linked oligosaccharides in glycoproteins are considerably more stable to mild alkali than are O-linked chains has been reexamined. A number of 'H-labeled model glycoproteins (fetuin, transferrin, and glycophorin) were treated with: (i) 0.05 M OH--l M BH; at 50°C for 16 h, (ii) 0.1 M OH--O.8 M BH, at 37°C for 68 h, and (iii) 1 M OH--4 M BH; at 80°C for 24 h. Analysis of the products by gel filtration and paper electrophoresis showed that both N-and O-linked chains were released by all three conditions. A portion (40%) of the asparagine-linked units produced under condition (i) remained as glycopeptides. Although mild alkaline borohydride cannot be used as a diagnostic reagent for distinguishing N-and 0-glycosides, it is a useful general procedure for the analysis of the carbohydrate moieties of glycoproteins. Application of the method to a differentiation antigen (gp 160) of human kidney epithelia is described.