Construction and characterization of a novel glucose dehydrogenase-leucine dehydrogenase fusion enzyme for the biosynthesis of L-tert-leucine.

Background: Biosynthesis of L-tert-leucine (L-tle), a significant pharmaceutical intermediate, by a cofactor regeneration system friendly and efficiently is a worthful goal all the time. The cofactor regeneration system of leucine dehydrogenase (LeuDH) and glucose dehydrogenase (GDH) has showed great coupling catalytic efficiency in the synthesis of L-tle, however the multi-enzyme complex of GDH and LeuDH has never been constructed successfully.

Results: In this work, a novel fusion enzyme (GDH-R3-LeuDH) for the efficient biosynthesis of L-tle was constructed by the fusion of LeuDH and GDH mediated with a rigid peptide linker.