Bioprocess-based Production of Glucaric Acid by Recombinant E. coli Strains

Glucaric acid was listed in the 2004 Department of Energy report as one of the “Top Value Added Chemicals from Biomass” with a $15-40 billion addressable market size.  Indeed, glucaric acid is a versatile C-6 diacid that can be produced from glucose, a renewable biomass-derived resource, and has a plethora of uses ranging from detergents to polymers.  Using the tools of synthetic biology, the Prather lab at MIT has developed engineered E. coli strains expressing the myo-Inositol 1-phosphate synthase (MIPS) from Saccharomyces cerevisiae, myo-inositol oxygenase (MIOX) from mouse, and uronate dehydrogenase (Udh) from the bacterium Pseudomonas syringae.  It is Kalion Inc.’s vision that glucaric acid can be produced by commodity scale fermentation of engineered E. coli, similar to other fermentation-produced commodities such as, diols, organic acids, and amino acids.  Kalion's internal process development efforts have resulted in a glucose fed-batch process that have improved glucaric acid fermentation titers by an order of magnitude over the original lab-scale batch process.  This bioprocess serves as the yard stick for evaluating newly constructed E. coli strains, possessing glucuronic and glucaric acid catabolism gene deletions, enhancements to the soluble expression of MIOX to increase activity, and manipulations to central metabolism allowing a greater flux of glucose-6-phosphate to glucaric acid.