Yang Lu, Zhu Jinmei, Sun Chenghai, Deng Zixin, Qu Xudong
State Key Laboratory of Microbial Metabolism , School of Life Sciences and Biotechnology , Shanghai Jiao Tong University , Shanghai 200240 , China . Email:
Key Laboratory of Combinatorial Biosynthesis and Drug Discovery Ministry of Education , School of Pharmaceutical Sciences , Wuhan University , Wuhan 430071 , China.
Chem Sci. 2019 Nov 18;11(2):364-371. doi: 10.1039/c9sc03773j. eCollection 2020 Jan 14.
Herein, we report a biocatalytic approach to synthesize plant tetrahydroisoquinoline alkaloids (THIQAs) from dihydroisoquinoline (DHIQ) precursors using imine reductases and -methyltransferase (NMT). The imine reductase IR45 was engineered to significantly expand its substrate specificity, enabling efficient and stereoselective conversion of 1-phenyl and 1-benzyl 6,7-dimethoxy-DHIQs into the corresponding ()-tetrahydroisoquinolines (-THIQs). Coclaurine -methyltransferase (CNMT) was able to further efficiently convert these ()-THIQ intermediates into ()-THIQAs. By assembling IRED, CNMT, and glucose dehydrogenase (GDH) in one reaction, we effectively constituted two artificial biosynthetic pathways in and successfully applied them to the production of five ()-THIQAs. This highly efficient (100% yield from DHIQs) and easily tailorable (adding other genes) biosynthetic approach will be useful for producing a variety of plant THIQAs.
在此，我们报道了一种生物催化方法，该方法使用亚胺还原酶和N-甲基转移酶（NMT）从二氢异喹啉（DHIQ）前体合成植物四氢异喹啉生物碱（THIQAs）。对亚胺还原酶IR45进行了工程改造，以显著扩大其底物特异性，从而能够将1-苯基和1-苄基6,7-二甲氧基-DHIQs高效且立体选择性地转化为相应的（）-四氢异喹啉（-THIQs）。古柯碱N-甲基转移酶（CNMT）能够进一步有效地将这些（）-THIQ中间体转化为（）-THIQAs。通过在一个反应中组装IRED、CNMT和葡萄糖脱氢酶（GDH），我们在大肠杆菌中有效地构建了两条人工生物合成途径，并成功地将它们应用于五种（）-THIQAs的生产。这种高效（从DHIQs的产率为100%）且易于定制（添加其他基因）的生物合成方法将有助于生产各种植物THIQAs。
