From Computational Screening to Preparative Scale: A Transaminase Identified by Machine Learning for (R)-1-Boc-3-aminopyrrolidine
摘要
(R)-( +)-1-Boc-3-aminopyrrolidine is an indispensable chiral intermediate for central nervous system drugs and Janus kinase inhibitors, yet its traditional chemical synthesis is plagued by harsh conditions, heavy pollution, and inadequate stereocontrol. Biocatalysis with transaminases (TAs) offers an attractive green alternative, but discovering optimal enzymes remains a major bottleneck. Here, we report a synergistic integration of machine learning (ML) with experimental validation to break this bottleneck. By ML-enabled evaluation of seven phylogenetically diverse TAs, we rapidly identified TA-6 from Arthrobacter sp. as an outstanding (R)-selective biocatalyst for the asymmetric amination of prochiral N-Boc-3-pyrrolidinone. Notably, using a whole-cell catalyst loading of only 10 g/L (DCW), TA-6 converted 100 g/L of ketone substrate on a 20-L preparative scale, delivering the desired (R)-enantiomer in 99.5% enantiomeric excess. This work not only provides a practical, scalable, and sustainable biocatalytic route to a pharmaceutically essential chiral amine, but also demonstrates that machine learning enables a paradigm shift from trial-and-error to data-driven precision in asymmetric synthesis, dramatically accelerating enzyme discovery.
Graphical Abstract