Department of Biological Sciences, Faculty of Agriculture, Yamaguchi University, Yoshida, Yamaguchi 753-8511, Japan.
Biotechnol Lett. 2012 Mar;34(3):475-81. doi: 10.1007/s10529-011-0784-4. Epub 2011 Nov 3.
A glucosyltransferase (GT) of Phytolacca americana (PaGT3) was expressed in Escherichia coli and purified for the synthesis of two O-β-glucoside products of trans-resveratrol. The reaction was moderately regioselective with a ratio of 4'-O-β-glucoside: 3-O-β-glucoside at 10:3. We used not only the purified enzyme but also the E. coli cells containing the PaGT3 gene for the synthesis of glycoconjugates. E. coli cell cultures also have other advantages, such as a shorter incubation time compared with cultured plant cells, no need for the addition of exogenous glucosyl donor compounds such as UDP-glucose, and almost complete conversion of the aglycone to the glucoside products. Furthermore, a homology model of PaGT3 and mutagenesis studies suggested that His-20 would be a catalytically important residue.
美洲商陆的葡萄糖基转移酶（GT）在大肠杆菌中表达并纯化，用于合成白藜芦醇的两种 O-β-葡萄糖苷产物。该反应具有中等的区域选择性，4'-O-β-葡萄糖苷与 3-O-β-葡萄糖苷的比例为 10:3。我们不仅使用了纯化的酶，还使用了含有 PaGT3 基因的大肠杆菌细胞来合成糖缀合物。与培养的植物细胞相比，大肠杆菌细胞培养物还有其他优点，例如孵育时间更短，不需要添加 UDP-葡萄糖等外源葡萄糖基供体化合物，并且几乎可以完全将苷元转化为糖苷产物。此外，PaGT3 的同源模型和突变研究表明，His-20 是一个催化上重要的残基。
