葡萄阿拉伯半乳聚糖蛋白结构的新研究。

New investigations of the structure of grape arabinogalactan-protein.

作者信息

Saulnier L, Brillouet J M, Moutounet M, Hervé du Penhoat C, Michon V

机构信息

Institut National de la Recherche Agronomique, Laboratoire des Polymères et des Techniques Physico-Chimiques, Montpellier, France.

出版信息

Carbohydr Res. 1992 Feb 7;224:219-35. doi: 10.1016/0008-6215(92)84108-5.

DOI:10.1016/0008-6215(92)84108-5

PMID:1591763

Abstract

The structure of an arabinogalactan-protein (AGP) isolated from grape juice was studied by methylation analysis, n.m.r. spectroscopy, and interactions with peanut lectin, after specific degradation with purified enzymes and/or Smith degradation. AGP appeared to be homogeneous with a weight-average molecular weight of 110,000. Treatment of AGP with arabinofuranosidase released 88% of the arabinose and left GP1. Hydrolysis of GP1 with an endo-(1----6)-beta-D-galactanase removed 50% of the galactose and left GP2. Smith degradation of GP1 gave a 3-linked galactan that still contained 3,6-linked residues. Endogalactanase- and Smith-degraded GP1, but not AGP and GP1, reacted strongly with peanut lectin. Thus, AGP is a 3-linked galactan cross-linked at positions 6. The core also carries, at positions 6, 6-linked galactan chains heavily 3-substituted with arabinofuranose residues.

摘要

通过甲基化分析、核磁共振光谱法以及在用纯化酶进行特异性降解和/或Smith降解后与花生凝集素的相互作用，对从葡萄汁中分离出的一种阿拉伯半乳聚糖蛋白（AGP）的结构进行了研究。AGP似乎是均一的，重均分子量为110,000。用阿拉伯呋喃糖苷酶处理AGP释放出88%的阿拉伯糖，剩余GP1。用内切-(1→6)-β-D-半乳聚糖酶水解GP1去除了50%的半乳糖，剩余GP2。GP1的Smith降解产生了一种仍含有3,6-连接残基的3-连接半乳聚糖。内切半乳聚糖酶和Smith降解的GP1，而非AGP和GP1，与花生凝集素强烈反应。因此，AGP是一种在6位交联的3-连接半乳聚糖。核心在6位还带有被阿拉伯呋喃糖残基大量3-取代的6-连接半乳聚糖链。