Structures of the Carbohydrate Moiety of Ovalbumin Glycopeptide III and the Difference in Specificity
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چکیده
Endo-P-N-acetylglucosaminidase C,, hydrolyzes 75% of ovalbumin glycopeptide III, while endo+N-acetylglucosaminidase H cleaves it completely. For the purpose of clarifying the difference of substrate specificities of C,, and H enzymes, the structures of the oligosaccharides released from the glycopeptide by these enzymes were studied. The oligosaccharides released by C,, enzyme were Mancul + 6 (Mancul + 3)Mancul -+ G(GlcNAcfi1 ---3 ZManal + 3) (GlcNAc/31+ 4)Man/31+ 4GlcNAc and Manal-+ ZMancYl --) G(Mancu1 + 3)Manal+ 6 (Mancul -2Mancul+ 3)Manpl + 4GlcNAc. Additional oligosaccharide, Mancul -+ 3Mancul + G[GlcNAc/312(GlcNAc/31+ 4) Manal--+ 31 (GlcNAcfil + 4)Manfil + 4GlcNAc, was released by H enzyme action. From these results, the important role of the cy-mannosyl residue linked at the C-3 position of the branching p-mannose for C,, enzyme action has become evident.
منابع مشابه
Structures of the carbohydrate moiety of ovalbumin glycopeptide III and the difference in specificity of endo-beta-N-acetylglucosaminidases CII and H.
Endo-P-N-acetylglucosaminidase C,, hydrolyzes 75% of ovalbumin glycopeptide III, while endo+N-acetylglucosaminidase H cleaves it completely. For the purpose of clarifying the difference of substrate specificities of C,, and H enzymes, the structures of the oligosaccharides released from the glycopeptide by these enzymes were studied. The oligosaccharides released by C,, enzyme were Mancul + 6 (...
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تاریخ انتشار 2002