蜂王浆糖蛋白N-聚糖中GalNAcbeta1-4GlcNAc单元的出现情况。

Occurrence of GalNAcbeta1-4GlcNAc unit in N-glycan of royal jelly glycoprotein.

作者信息

Kimura Mariko, Hama Yoichiro, Tsumura Kazunori, Okihara Kiyoshi, Sugimoto Hiroyuki, Yamada Hideo, Kimurai Yoshinobu

机构信息

Department of Bioresources Chemistry, Faculty of Agriculture, Okayama University, Japan.

出版信息

Biosci Biotechnol Biochem. 2002 Sep;66(9):1985-9. doi: 10.1271/bbb.66.1985.

DOI:10.1271/bbb.66.1985

PMID:12400705

Abstract

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 GalNAc as; GlcNAc(beta)1-2Man(alpha)1-6(GalNAcbeta1 - 4GIcNAcbeta1 - 2Man(alpha)1 - 3)Manbeta1 - 4GlcNAc(beta)1-4GlcNAc. This result suggested that a beta1-4 GalNAc transferase is present in hypopharyngeal and mandibular glands of honeybees.

摘要

在其他研究中，我们对从蜂王浆糖蛋白中纯化得到的12种N - 聚糖的结构进行了表征（木村洋等人，《生物科学、生物技术与生物化学》，64卷，2109 - 2120页（2000年））。结构分析表明，典型的高甘露糖型结构（Man9 - 4GlcNAc2）约占总N - 聚糖的72%，双天线型结构（GlcNAc2Man3GlcNAc2）约占8%，杂合型结构（GlcNAc1Man4GlcNAc2）约占3%。在对蜂王浆糖蛋白的次要N - 聚糖进行结构分析时，我们发现其中一种在非还原端有一个N - 乙酰半乳糖胺残基；大多数此类残基已在哺乳动物糖蛋白的N - 聚糖中发现。通过外切糖苷酶消化、甲基化分析、离子喷雾（IS） - MS分析和1H NMR光谱分析，我们确定了含有GalNAc的N - 聚糖的结构为：GlcNAc(β)1 - 2Man(α)1 - 6(GalNAcβ1 - 4GIcNAcβ1 - 2Man(α)1 - 3)Manβ1 - 4GlcNAc(β)1 - 4GlcNAc。这一结果表明，蜜蜂下咽腺和下颚腺中存在β1 - 4 GalNAc转移酶。