A new metabolic route for the fermentative production of 5-aminovalerate from glucose and alternative carbon sources

Abstract

Here, a new metabolic pathway for the production of 5-aminovalerate (5AVA) from l-lysine via cadaverine as intermediate was established and this three-step-pathway comprises l-lysine decarboxylase (LdcC), putrescine transaminase (PatA) and γ-aminobutyraldehyde dehydrogenase (PatD). Since Corynebacterium glutamicum is used for industrial l-lysine production, the pathway was established in this bacterium. Upon expression of ldcC, patA and patD from Escherichia coli in C. glutamicum wild type, production 5AVA was achieved. Enzyme assays revealed that PatA and PatD also converted cadaverine to 5AVA. Eliminating the by-products cadaverine, N-acetylcadaverine and glutarate in a genome-streamlined l-lysine producing strain expressing ldcC, patA and patD improved 5AVA production to a titer of 5.1gL^-1, a yield of 0.13gg^-1 and a volumetric productivity of 0.12gL^-1h^-1. Moreover, 5AVA production from the alternative feedstocks starch, glucosamine, xylose and arabinose was established.

Keywords: 5-Aminovalerate; Corynebacterium glutamicum; Gamma-aminobutyraldehyde dehydrogenase; Polyamide; Putrescine transaminase.