Metabolic engineering of Enterobacter aerogenes to improve the production of 2,3-butanediol

Abstract The enhanced production of 2,3-butanediol was investigated using a metabolic engineering approach and optimized fermentation conditions. New engineered strains of Enterobacter aerogenes ATCC 29007 were developed by deleting the d - lactate dehydrogenase ( ldh A), phosphate acetyltransferase ( pta ), malate dehydrogenase ( mdh ), and acetaldehyde dehydrogenase ( acdh ) genes to block the production of lactate, acetate, succinate, and ethanol, respectively. The resulting engineered strain E. aerogenes SUMI02 (Δ ldh AΔ pta ) produced 36.5 g/L of 2,3-butanediol in flask cultivation, an amount 8.11 times greater than that of its wild type counterpart (4.5 g/L). In addition, the 2,3-butanediol production and productivity reached 38.24 g/L and 0.8 g/L/h, respectively, in the batch fermentation using a bioreactor.