Efficient fumaric acid production using E. coli with a re-designed TCA cycle

Abstract

In this work, E. coli was engineered to produce fumaric acid. The iclR gene was deletedto redirect the carbon flux through the glyoxylate shunt. This, together with the deletionof fumA, fumB and fumC, resulted in production of fumaric acid to 1.45 g/L. Plasmidbasedoverexpression of the ppc gene further increased the titer to 4.09 g/L. Next,arcA and ptsG were deleted to reinforce the oxidative TCA cycle, and aspA was deletedto block the conversion of fumaric acid to L-aspartate. Finally, galP was overexpressedto improve the glucose uptake. Fed-batch culture of the final strain produced a fumaricacid titer of 28.2 g/L. [This work was supported by the Technology DevelopmentProgram to Solve Climate Changes on Systems Metabolic Engineering for Biorefineriesfrom the Ministry of Science, ICT and Future Planning (MSIP) through the NationalResearch Foundation (NRF) of Korea. MG was additionally supported by the Swedish research council Formas]