Construction of novel molecular mechanism on polysaccharide-forming enzyme and its application

本研究的目的是阐明产多糖酶和中型寡糖酶的结构要素。此外，通过控制结构元件形成新的低聚糖也是本研究的目的。所得结果如下：(1)多糖产生酶：催化氨基酸为两个Glu。形成多糖的结构元件位于酶的c端区。(2)中等大小寡糖生成酶：三维结构明确，催化残基为Asp和Glu。对远离催化中心的两个芳香残基的突变分析表明，其中一个残基改善了酶的功能。

Purpose of this research is the elucidation of structural elements of polysaccharide-producing enzyme and middle-size-oligosaccharide-producing enzyme. Furthermore, the formation of new oligosaccharide is also purpose of this study by controlling the structural element. The obtained results were as follows; (1) Polysaccharide-producing enzyme: Catalytic amino acids were two Glu. Polysaccharide-forming structural element was in the C-terminal region of enzyme. (2) Middle-size-oligosaccharide-producing enzyme: Three-dimensional structure was elucidated, and catalytic residues were Asp and Glu. Mutation analyses of two aromatic residues at sites distant from catalytic center revealed that one residue improved the enzyme function.