Occurrence of GalNAcbeta1-4GlcNAc unit in N-glycan of royal jelly glycoprotein
2002
"Kimura, M. (Okayama Univ. (Japan). Faculty of Agriculture) | Hama, Y. | Tsumura, K. | Okihara, K. | Sugimoto, H. | Yamada, H. | Kimura, Y. "
"Elsewhere, we characterized the structure of twelve N-glycans purified from royal jelly glycoproteins (Kimura, Y. et al., Biosci. Biotechnol. Biochem., 64, 2109-2120 (2000)). Structural analysis showed that the typical high-mannose type structure (Man9-4GlcNAc2) accounts for about 72% of total N-glycans, a biantennary-type structure (GlcNAc2Man3GlcNAc2) about 8%, and a hybrid-type structure (GlcNAc1Man4GlcNAc2) about 3%. During structural analysis of minor N-glycans of royal jelly glycoproteins, we found that one had an N-acetyl-galactosaminyl residue at the non reducing end; most of such residues have been found in N-glycans of mammalian glycoproteins. By exoglycosidase digestion, methylation analysis, ion-spray (IS)-MS analysis, and 1H NMR spectroscopy, we identified the structure of the N-glycan containing GaINAc as; GIcNAcbeta1-2Manalpha1-6(Gal-NAcbeta1-4GIcNAcbeta1-2Manalpha1-3)Manbeta1-4GIcNACbeta1-4GIcNAc. This result suggested that a beta1-4GaINAc transferase is present in hypopharyngeal and mandibular glands of honeybees. "
اظهر المزيد [+] اقل [-]