Self-sufficient flow-biocatalysis by coimmobilization of pyridoxal 5′-phosphate and ω-transaminases onto porous carriers

We expanded the application of self-sufficient heterogeneous biocatalysts containing coimmobilized ω-transaminases and pyridoxal 5′-phosphate (PLP) to efficiently operate packed-bed reactors in continuous flow. Using a ω-transaminase from Halomonas elongata coimmobilized with PLP onto porous methacrylate-based carriers coated with polyethylenimine, we operated a packed-bed reactor continuously for up to 50 column volumes at 1.45 mL × min–1 in the enantioselective deamination of model amines (α-methylbenzyl amine), yielding >90% conversion in all cycles without exogenous addition of cofactor. In this work, we expanded the concept of self-sufficient heterogeneous biocatalysts to other ω-transaminases such as the ones from Chromobacterium violaceum and Pseudomonas fluorescens. We found that enzymes with lower affinities toward PLP present lower operational stabilities in flow, even when coimmobilizing PLP. Furthermore, ω-transaminases coimmobilized with PLP were successfully implemented for the continuous synthesis of amines and the sustainable metrics were assessed. These results give some clues to exploit PLP-dependent ω-transaminases under industrially relevant continuous operations in a more cost-effective and environmentally friendly process.We want to acknowledge ARAID foundation for funding F.L.G. and to MINECO (BIO2015-69887-R) for funding A.I.B.M and F.L.G. This work was also supported for M.L.C. and F.P. by BBSRC [grant number BB/P002536/1]. F.L.G. and F.P. thank the support of COST action CM1303-System biocatalysis that made possible this collaborative research funding A.I.B.M. short-stay at University of Nottingham. S.V.L. is grateful for the postdoctoral fellowship received from the Mexican Council for Science and Technology (CONACyT).Peer reviewe