We constructed enzyme variants of the α-glucosidases from Aspergillus oryzae (AoryAgdS) and Aspergillus sojae (AsojAgdL) by mutating the amino acid residue at position 450. AoryAgdS_H450R acquired the ability to produce considerable amounts of α-1,6-transglucosylation products, whereas AsojAgdL_R450H changed to produce more α-1,3- and α-1,4-transglucosylation products than α-1,6-products. The 450th amino acid residue is critical for the transglucosylation of these α-glucosidases.

中文翻译：

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通过单一的关键氨基酸置换修饰来自米曲霉和酱油曲霉的 α-葡糖苷酶的转葡糖基化特性。

我们通过突变第 450 位的氨基酸残基构建了来自米曲霉 (AoryAgdS) 和酱油曲霉 (AsojAgdL) 的 α-葡萄糖苷酶的酶变体。 AoryAgdS_H450R 获得了产生大量 α-1,6- 转葡萄糖基化产物的能力， AsojAgdL_R450H 改变为产生比 α-1,6-产物更多的 α-1,3- 和 α-1,4- 转葡萄糖基化产物。第 450 个氨基酸残基对于这些 α-葡糖苷酶的转葡糖基化至关重要。