GLYCOPEPTIDES ISOLATED FROM SERICIN OF THE SILKWORM, BOMBYX-MORI

1. 1. Sericin of the silkworm, Bombyx mori, was extensively digested with pronase, and three glycopeptides were isolated by chromatography on ion-exchange resins, Bio-Gel, and charcoal. 2. 2. Structural analyses of these glycopeptides with digestion by specific glycosidases and Smith degradation indicate that sericin contains two types of carbohydrate units. 3. 3. One type contains the carbohydrate units which consist of either N-acetylgalactosamine alone or a disaccharide, β-galactosyl(l → 3)-N-acetylgalactosamine, and which are linked to peptide core with an alkali-labile O-glycosidic bond between N-acetylgalactosamine and serine or threonine. 4. 4. The other type contains the carbohydrate units which consist of several mannose residues and two N-acetylglucosamine residues, and which are linked to peptide core with an alkali-stable N-glycosidic bond between N-acetylglucosamine and asparagine. © 1979.