Co-production of acetoin and succinic acid using corncob hydrolysate by engineered Enterobacter cloacae

Abstract

To improve the synthesis of succinic acid and acetoin, 2,3-butanediol dehydrogenase, lactate dehydrogenase, pyruvate formate-lyase, and glucose transporter EIIBCGlc genes were deleted from the Enterobacter cloacae genome to construct the CL82 strain. The CL82 strain co-production concentrations of succinic acid and acetoin from glucose within 48 h were 15.41 and 36.95 g L-1, the succinic acid and acetoin productivity were 0.32 and 0.77 g L-1h−1, respectively, and the amount of added bicarbonate was reduced by 38.6%. Moreover, CL82 can also co-utilize glucose and xylose for the co-production of succinic acid and acetoin during fermentation. CL82 can also utilize corncob hydrolysate for the co-production of succinic acid and acetoin. The engineering strategy presented herein can provide a practical approach for the utilization of renewable feedstocks foe the simultaneous production of two commercial products using CL82, which helps to reduce the cost of microbial fermentation.