Imine Reductase Based All-Enzyme Hydrogel with Intrinsic Cofactor Regeneration for Flow Biocatalysis

oleh: Patrick Bitterwolf, Felix Ott, Kersten S. Rabe, Christof M. Niemeyer

Format: Article
Diterbitkan: MDPI AG 2019-11-01

Deskripsi

All-enzyme hydrogels are biocatalytic materials, with which various enzymes can be immobilized in microreactors in a simple, mild, and efficient manner to be used for continuous flow processes. Here we present the construction and application of a cofactor regenerating hydrogel based on the imine reductase GF3546 from <i>Streptomyces</i> sp. combined with the cofactor regenerating glucose-1-dehydrogenase from <i>Bacillus subtilis</i>. The resulting hydrogel materials were characterized in terms of binding kinetics and viscoelastic properties. The materials were formed by rapid covalent crosslinking in less than 5 min, and they showed a typical mesh size of 67 &#177; 2 nm. The gels were applied for continuous flow biocatalysis. In a microfluidic reactor setup, the hydrogels showed excellent conversions of imines to amines for up to 40 h in continuous flow mode. Variation of flow rates led to a process where the gels showed a maximum space-time-yield of 150 g&#183;(L&#183;day)<sup>&#8722;1</sup> at 100 &#956;L/min.