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

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(-1)h(-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. (c) 2022 Elsevier Ltd. All rights reserved.

Automated summary

By genetically engineering the Enterobacter cloacae genome, the CL82 strain was constructed for the co-production of succinic acid and acetoin. CL82 showed high concentrations and productivities of succinic acid and acetoin from glucose, and could also utilize xylose and corncob hydrolysate for co-production. This engineering strategy provides a practical approach for simultaneous production of two commercial products using renewable feedstocks, reducing the cost of microbial fermentation.