通过两个莱克的分子识别sialyl Lewis (x) 和相关的糖化物
T Haselhorst1, T Weimar, T Peters
1Institut für Chemie, Medizinische Universität zu Lübeck, Ratzeburger Allee 160, D-23538 Lübeck, Germany.
Journal of the American Chemical Society
|October 25, 2001
概括
这项研究调查了sialyl Lewis (x),Lewis (x) 和alpha-L-Fuc-{1-->3) -beta-D-GlcNAc与莲花四角虫学蛋白A (LTL-A) 和阿勒亚兰地亚聚素 (AAA) 的结合. 研究人员发现,L-糖残留是结合的关键,在莱克复合体中观察到不同的方向.
科学领域:
- 碳水化合物化学 碳水化合物化学
- 葡萄糖生物学 葡萄糖生物学
- 结构生物学 结构生物学
背景情况:
- 乳清素是能结合碳水化合物的蛋白质,在生物识别中起作用.
- 含有糖的甘氨酸如sialyl Lewis (x) 和Lewis (x) 在细胞粘附和免疫反应中很重要.
- 莲花四角虫学蛋白A (LTL-A) 和Aleuria aurantia聚合素 (AAA) 是糖结合学蛋白,具有潜在的诊断和治疗应用.
研究的目的:
- 阐明特定的含碳水化合物与两种不同的单蛋白 (LTL-A和AAA) 之间的结合相互作用.
- 为了确定这些碳水化合物-乳素复合物的生物活性构造和表观图映射.
- 为了比较这些相互作用的结合亲缘关系和结构后果.
主要方法:
- 核磁共振 (NMR) 谱学,包括trNOESY,QUIET-trNOESY和trROESY,以确定生物活性构成.
- 表面等离子共振 (SPR) 用于量化结合亲缘关系 (解离常数).
- STD NMR实验用于结合碳水化合物的表位映射.
主要成果:
- 无论是LTL-A还是AAA都与alpha-L-Fuc-(1-->3) -beta-D-GlcNAc和Lewis ((x) 结合;只有AAA与sialyl Lewis ((x) 结合.
- 结合亲和力下降的顺序是:α-L-Fuc-(1-->3) -β-D-GlcNAc > 易斯(x) > sialyl Lewis(x) 对于两个莱克.
- 在Lewis (x) 和sialyl Lewis (x) 复合物中观察到异常的糖残留方向,L-糖残留与莱克直接接触.
结论:
- L-糖部分是LTL-A和AAA的主要相互作用部位.
- 立体相互作用会影响与AAA结合时,sialyl Lewis中的酸的方向.
- 该研究提供了有关碳水化合物-乳酸蛋白识别的详细结构见解,这与理解生物过程和开发基于乳酸蛋白的工具有关.
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