Biosynthesis of diverse Ephedra-type alkaloids via a newly identified enzymatic cascade
Peiling Wua, Ding Luo b, Yuezhou Wang a, Xiaoxu Shang a, Binju Wang b, Xianming Deng a, Jifeng Yuan*ac
a State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Fujian 361102, China
b College of Chemistry and Chemical Engineering, Xiamen University, Fujian 361005, China
c Shenzhen Research Institute of Xiamen University, Shenzhen 518057, China
* Corresponding author Email address: jfyuan@xmu.edu.cn
Abstract
Ephedra-type alkaloids represent a large class of natural and synthetic phenylpropanolamine molecules with great pharmaceutical values. However, the existing methods typically reply on chemical approaches to diversify the N-group modification of Ephedra-type alkaloids. Herein, we report a two-step enzymatic assembly line for creating structurally diverse Ephedra-type alkaloids, to replace the conventional chemical modification steps. We first identified a new carboligase from Bacillus subtilis (BsAlsS, acetolactate synthase) as a robust catalyst to yield different phenylacetylcarbinol (PAC) analogs from diverse aromatic aldehydes with near 100% conversions. Subsequently, we screened imine reductases (IREDs) for the reductive amination of PAC analogs. It was found that IRG02 from Streptomyces albidoflavus had good activities with conversions ranging from 37%~84% for the reductive alkylamination with diverse amine partners such as allylamine, propargylamine and cyclopropylamine. Overall, three new bio-modifications at the N-group of Ephedra-type alkaloids were established. Taken together, our work lays a foundation for the future implementation of biocatalysis for synthesizing structurally diverse Ephedra-type alkaloids with potential new pharmaceutical applications.
Keywords: Ephedra-type alkaloids; structural diversity; catabolic acetolactate synthase; imine reductase; reductive alkylamination; biocatalysis
全文连接: https://spj.science.org/doi/10.34133/bdr.0048