Metabolic Engineering of for Production of Acetoin.

Acetoin is a potential platform compound for a variety of chemicals. MW3, a thermophilic and generally regarded as safe (GRAS) microorganism, can produce 2,3-butanediol with a high concentration, yield, and productivity. In this study, MW3 was metabolic engineered for acetoin production. After deleting two 2,3-butanediol dehydrogenases encoding genes and , an engineered strain MW3 (ΔΔ) was constructed. Using fed-batch fermentation of MW3 (ΔΔ), 64.2 g/L acetoin was produced at a productivity of 2.378 g/[L h] and a yield of 0.412 g/g from 156 g/L glucose in 27 h. The fermentation process exhibited rather high productivity and yield of acetoin, indicating that MW3 (ΔΔ) might be a promising acetoin producer.