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紫云英根瘤菌107菌株酸性胞外多糖的分离纯化及结构分析

吴min, 周蓓芸, 宋鸿遇, 郭忠武, 王来曦

中科院上海植物生理研究所.上海 200032；中科院上海有机化学研究所.上海 200032

摘要

紫云英根瘤菌野生型107菌株与NA02(R^-11)产生的EPS糖组分均由葡萄糖、半乳糖、核糖和葡萄糖醛酸构成;而变种NA02产生的EPS只含葡萄糖、半乳糖和葡萄糖醛酸,与野生型显著不同。3个菌株的EPS均有乙酰基取代,而无其它形式的取代基。EPS的酸性来自葡萄糖醛酸。~(1)H-NMR分析表明,野生型菌株107和回复子NA02(R^-11)的EPS糖残基通过#alpha#和#beta#糖苷键方式连接,而变种NA02 EPS的糖链中均为#alpha#连接方式。

关键词： 紫云英根瘤菌; 分离; 纯化; 酸性胞外多糖

Isolation, purification and structure analysis of acidic exopolysaccharide from Rhizobium astragali strain 107

Wu Min, Zhou Beiyun, Song Hongyu, Guo Zhongwu, Wang Laixi

Shanghai Institute of Plant Physiology,The Chinese Academy of Sciences.Shanghai 200032；China

Abstract

The acidic exopolysaccharides (EPS) of R. astragali wild type 107, its Exo~(-) mutant NA02 and R^plasmid transconjugant NAO2 CR^-11) were isolated and purified by acetone precipitation and chromatography. Their composition and structure were also studied using ~(1)H-NMR, infrared spectrum, gas choromatography, TCL. The EPS of R. astragali contained only a high-molecular-weight fraction of EPS, and no low-molecular-weight oligosaccharides were detected. Strain 107 and NA02 (R^-11) produce identical EPS which consists of glucose, galactose, ribose and glucuronic acid and links with #alpha# and #beta# linkages. In contrast, the EPS secreted by mutant NA02 lacks in ribose and the sugar residues were linked by the same #beta# linkages. All of the EPSs contain only acetyl substitutent, and the EPSs^ acidic nature comes from the uronic acid.

Key words: Rhizobium astragali;Isolation;Purification;Exopolysaccharides

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引用本文：

吴min, 周蓓芸, 宋鸿遇, 郭忠武, 王来曦. 紫云英根瘤菌107菌株酸性胞外多糖的分离纯化及结构分析[J]. 生理学报 1997; 49 (3): .

Wu Min, Zhou Beiyun, Song Hongyu, Guo Zhongwu, Wang Laixi. Isolation, purification and structure analysis of acidic exopolysaccharide from Rhizobium astragali strain 107. Acta Physiol Sin 1997; 49 (3): (in Chinese with English abstract).