Studies on the Hydrazinolysis of Glycoproteins
Core Structures of Oligosaccharides Obtained from Porcine Thyroglobulin and Pineapple Stem Bromelain
1976 年 80 巻 6 号 p. 1223-1232
詳細
1976 年 80 巻 6 号 p. 1223-1232
Hydrazinolysis of porcine thyroglobulin glycopeptides and of pineapple stem bromelain [EC 3.4.22.4] permitted the isolation of almost intact carbohydrate chains of these glycoproteins. On the basis of permethylation analyses of the released oligosaccharides after reduction with NaBH4, the core structures of Unit A-type and Unit B-type carbohydrate chains of porcine thyroglobulin were deduced to be Manαl→6 [Manαl→3] Manβl→4G1cNAcβ1→4 [Rαl→6] GlcNAc→Asn (Unit A-type, R=H; Unit B-type, R=Fuc), and that of bromelain was found to be Manαl→6 [R'1→2] Manβ1→4G1cNAcβ1→4 [R1→3] G1cNAc→Asn (R'=Xy1β and R=Fucα, or R'=Fucα and R=Xylβ). From these results, it appears that the hydrazinolysis method is applicable to a wide variety of glycoproteins which have an N-glycosylamine linkage between the carbohydrate and peptide moieties, regardless of the type of linkage to the most proximal N-acetylglucosamine residue which is bound to asparagine.
