作　　者： ; ; ; ;

机构地区： 中南林业科技大学食品科学与工程学院

出　　处： 《计算机与应用化学》 2010年第5期577-581,共5页

摘　　要： α-葡萄糖苷酶是生物体中一类非常重要的酶,在初级代谢及复合糖的生物合成与加工上具有重要作用。α-葡萄糖苷酶在自然界广泛分布,种类繁多,但目前对其分子结构和催化机制的了解还非常有限,因此预测并比较不同来源的α-葡萄糖苷酶结构的共性和个性具有重要的科学价值。本文从Swiss-Prot数据库中选取了4种典型微生物来源的α-葡萄糖苷酶,以EMBOSS和Clustal W在线工具比较了其基本参数和蛋白质序列,以Modeller软件预测了其三级结构,并用Castp服务器预测了它们的活性位点。根据其系统发育树和三维结构的相似性,这4种α-葡萄糖苷酶可分为AglA和YihQ,Bce33和Mal12 2组;构成它们活性位点pocket的氨基酸残基差异较大,但关键残基都由2个天冬氨酸、1个谷氨酸构成,而且AglA和YihQ,Bce33和Mal12的催化三联体在空间构象上几乎完全相似,表明它们的底物特异性和催化机制具有共性。为更好地理解α-葡萄糖苷酶的作用模式和研究其生物学功能提供了参考。 The α-glucosidases, which are widely distributed in the nature but with ess information about their molecular structure and catalytic mechanism. They are a particularly important subset of these enzymes in live organisms, both in primary metabolism and in glycoconjugate biosynthesis and processing. In this paper, the structure and active site of four α-glucosidases from different microbial origin was predicted and contrasted, using the soft Modeller and the web servers of Castp. The results showed that they can be divided into two groups, AglA and YihQ, Bce33 and Mall2, and were vary from the tertiary structure and active site pocket, but their catalytic triad was similarly formed by two aspartic acids （D） and one glutamic acid （E）, indicating they might share similar mode of action. These findings will provide theoretical basis for better understanding or researching on the catalytic mechanism and biological function of α-glucosidase.

关 键 词： 葡萄糖苷酶 结构 预测 活性位点 催化机制

领　　域： [生物学]