Abstract
An endo-β-N-acetylglucosaminidase has been purified to homogeneity from mature seeds of Ginkgo biloba. The molecular mass of the endo-β-N-acetylglucosaminidase, named Endo-GB, was estimated to be around 63 kDa by SDS-PAGE and around 62 kDa by Hiprep S-200 chromatography, respectively. The substrate specificity has been explored with regard to the pyridylaminated N-glycans. Several high mannose-type sugar chains bearing ケ-1,2-mannosyl residue(s), Man9-6GlcNAc2-PA, were the most favored substrates followed by Man5GlcNAc2-PA and a typical hybrid-type structure (GlcNAc1Man5GlcNAc2-PA) which does not bear an α-1,2-mannosyl residue. On the contrary, endo-GB could hardly hydrolyze the common core pentasaccharide of N-glycan (Man3GlcNAc2-PA) and the xylose-containing sugar chains (Man4-3Xyl1GlcNAc2-PA, Man3Fuc1Xyl1GlcNAc2-PA) being widely distributed in plant glycoproteins. Furthermore, we analyzed the structures of N-glycans conjugated to storage glycoproteins in the mature Ginkgo seeds to see the occurrence of endogenous substrates for Endo-GB. The structural analysis showed, however, only xylose-containing type N-glycans (Man3Fuc1Xyl1GlcNAc2 (95%) and Man3Xyl1GlcNAc2 (5%)), which can not be substrate for Endo-GB, predominantly occur in the storage glycoproteins.
Original language | English |
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Pages (from-to) | 253-261 |
Number of pages | 9 |
Journal | Bioscience, Biotechnology and Biochemistry |
Volume | 62 |
Issue number | 2 |
DOIs | |
Publication status | Published - Jan 1 1998 |
Keywords
- Endo-β-N-acetylglucosaminidase
- Ginkgo biloba
- N-glycan releasing enzyme
- N-glycan structure
- Plant glycoprotein
ASJC Scopus subject areas
- Biotechnology
- Analytical Chemistry
- Biochemistry
- Applied Microbiology and Biotechnology
- Molecular Biology
- Organic Chemistry