Immobilization of Microbial Consortium for Glutaric Acid Production from Lysine

Abstract

Glutaric acid is an important C5 platform compound for the synthesis of nylon polymers. However, its production titer and cost are limited by the need for expensive cofactors addition as well as the difficulty of reusing microbial catalysts. Herein, to address these problems, two regeneration systems each for NAD(P) + and α-ketoglutaric acid were introduced into a fiveenzyme cadaverine pathway for a whole-cell biocatalytic approach. We demonstrated the efficient conversion of lysine to glutaric acid in a synthetic microbial consortium manner, producing 73.2 g/L glutaric acid with a 74 % molar yield in a 5-L bioreactor scale. Moreover, with a colloidal chitin-based immobilization, the engineered microbial consortium exhibited good stability and reusability in a five-cycle bioconversion. This study provides an efficient microbial platform for glutaric acid production by developing a cheaper and universal cell immobilization approach.

Systems engineering of Escherichia coli for high-level glutarate production from glucose

“…Glutarate is a C5 dicarboxylic acid primarily used for the production of polyesters and polyamides 1,2 . It can be synthesized using different petroleum-based chemical methods, including (i) nitric acid oxidation of 2-cyanocylopentanone, (ii) condensation of acrylonitrile with ethyl malonate, (iii) ozonation of cyclopentane and permanganate cleavage of ozonide, and (iv) oxidation of pentamethylene glycol using nitrogen tetroxide [3][4][5] .…”