Construction of a Self-Purification and Self-Assembly Coenzyme Regeneration System for the Synthesis of Chiral Drug Intermediates

As one of the important research contents of synthetic biology, the construction of a regulatory system exhibits great potential in the synthesis of high value-added chemicals such as drug intermediates. In this work, a self-assembly coenzyme regeneration system, leucine dehydrogenase (LeuDH)–formate dehydrogenase (FDH) protein co-assembly system, was constructed by using the polypeptide, SpyTag/SpyCatcher. Then, it was demonstrated that the nonchromatographic inverse transition cycling purification method could purify intracellular coupling proteins and extracellular coupling proteins well. The conversion rate of the pure LeuDH–FDH protein assembly (FR-LR) was shown to be 1.6-fold and 32.3-fold higher than that of the free LeuDH–FDH system (LeuDH + FDH) and free LeuDH, respectively. This work has paved a new way of constructing a protein self-assembly system and engineering self-purification coenzyme regeneration system for the synthesis of chiral amino acids or chiral α-hydroxy acids.