Abstract:

Phosphinothricin (PPT) is one of the top three herbicides, known for its broad spectrum, high herbicidal activity, and non-selectivity, with a highly optimistic market prospect. However, PPT exists in two enantiomers (D-PPT and L-PPT), with the herbicidal activity primarily stemming from L-PPT. Therefore, efficient synthesis of high optical purity L-PPT is crucial.Pesticide manufacturing enterprises have attempted to develop chemical synthesis methods for L-PPT using approaches such as racemic compound splitting, asymmetric synthesis, natural amino acid chiral source method, and chiral auxiliary induction. However, due to challenges such as low stereo-selectivity, low product yield, and high production costs, large-scale production has not been achieved.Under the guidance of Academician Yin-Chu Shen, the "Father of Biopesticides in China", our research group has conducted scientific research and industrial practice on the biosynthesis of L-PPT for over 20 years. In cooperation with multiple enterprises, we have developed more than ten process routes and technologies. Among them, five routes (racemic mixture derivatization-resolution route, racemic PPT-chiral separation route, generic compound cyanation followed by hydrolysis route, de novo synthesis from common chemicals route, and synthesis of homoserine followed by chemical synthesis) are discussed in detail in this review. Each route's reconstruction, establishment of bioinorganic amine technology, creation of biocatalysts, high-density fermentation for enzyme production, product separation and purification, and reaction equipment are included. Notably, we developed the BioHiPP™, a biomanufacturing technology for the synthesis of highly optically pure L-PPT. Based on this technology, a ten-thousand-ton digital and intelligent production line for L-PPT was established. Utilizing smart sensors and actuators, real-time data collection, transmission, analysis, and feedback adjustment were achieved at over a thousand control points. This led to fully automated parameter collection and control, increasing production efficiency by 50% and reducing labor intensity by more than 70%, thereby realizing the bio-intelligent manufacturing of ten thousand tons of L-PPT.Based on the long-term accumulation of our research group, we summarize and analyze the mainstream production processes of D,L-PPT, detailing on the principles and methods of biomanufacturing technology and synthetic biology to construct the key synthesis system for L-PPT. We also compare the characteristics and key points of industrialization implementation of these routes in terms of substrate synthesis and selection, types of biocatalysts, use of amino donors, and separation and purification.It is foreseeable that, with the aid of synthetic biology technology, an increasing number of high-optical-purity chiral pesticides will be produced on a large scale through biomanufacturing in the future.

Key words: L-phosphinothricin, Biocatalysis, Enzyme, Chiral amino acid, Synthetic Biomanufacturing

摘要：

草铵膦是全球三大除草剂之一，具有广谱、活性高、非选择性等特点，市场前景被广泛看好。然而，草铵膦具有两种对映异构体（D型和L型），其除草活性主要来自于其中的L型对映体（L-草铵膦）。因此，高光学纯L-草铵膦高效合成至关重要。笔者研究团队在中国“生物农药之父”沈寅初院士的指导下，开展生物合成L-草铵膦的科学研究和产业化实践长达20余年，涵盖合成路线重构、生物无机胺化技术建立、生物催化剂创制、产物分离纯化、反应装备、过程智能化控制等方面，开发了“生物高纯精草生产技术（BioHiPP ^TM）”，建成了万吨级L-草铵膦数字智能化生产线，利用智能传感器和执行器，实现超千个控制点的实时数据采集、传输、分析和反馈调节，全自动化参数采集与控制生产效率提高50%，劳动强度降低70%以上，实现了万吨级L-草铵膦的生物智能制造。本文在研究团队长期积累的基础上，总结和分析了D，L-草铵膦主流生产工艺路线，详述了创新生物制造技术、合成生物技术构筑L-草铵膦关键合成体系的原理和方法，从底物合成与选择、生物催化剂类型、氨基供体使用、分离纯化等方面比较了这些路线的各自特点及实现产业化的关键要点。可以预见，在合成生物技术的助力下，未来将有越来越多的高光学纯度手性农药通过生物制造实现大规模生产。

关键词: D, L-草铵膦, L-草铵膦, 手性氨基酸, 合成生物制造