Improved -Butanol Production from Clostridium cellulovorans by Integrated Metabolic and Evolutionary Engineering.

DSM 743B offers potential as a chassis strain for biomass refining by consolidated bioprocessing (CBP). However, its -butanol production from lignocellulosic biomass has yet to be demonstrated. This study demonstrates the construction of a coenzyme A (CoA)-dependent acetone-butanol-ethanol (ABE) pathway in by introducing and genes from ATCC 824, which enabled it to produce -butanol using the abundant and low-cost agricultural waste of alkali-extracted, deshelled corn cobs (AECC) as the sole carbon source. Then, a novel adaptive laboratory evolution (ALE) approach was adapted to strengthen the -butanol tolerance of to fully utilize its -butanol output potential. To further improve -butanol production, both metabolic engineering and evolutionary engineering were combined, using the evolved strain as a host for metabolic engineering. The -butanol production from AECC of the engineered was increased 138-fold, from less than 0.025 g/liter to 3.47 g/liter. This method represents a milestone toward -butanol production by CBP, using a single recombinant clostridium strain. The engineered strain offers a promising CBP-enabling microbial chassis for -butanol fermentation from lignocellulose. Due to a lack of genetic tools, DSM 743B has not been comprehensively explored as a putative strain platform for -butanol production by consolidated bioprocessing (CBP). Based on the previous study of genetic tools, strain engineering of for the development of a CBP-enabling microbial chassis was demonstrated in this study. Metabolic engineering and evolutionary engineering were integrated to improve the -butanol production of from the low-cost renewable agricultural waste of alkali-extracted, deshelled corn cobs (AECC). The -butanol production from AECC was increased 138-fold, from less than 0.025 g/liter to 3.47 g/liter, which represents the highest titer of -butanol produced using a single recombinant clostridium strain by CBP reported to date. This engineered strain serves as a promising chassis for -butanol production from lignocellulose by CBP.