Characterization of a butanol-acetone-producing Clostridium strain and identification of its solventogenic genes.

abstract A unique Clostridium species strain G117 was obtained in this study to be capable of producing dominantbutanol from glucose. Butanol of 13.50 g/L was produced when culture G117 was fed with 60 g/L glucose,which is 20% higher than previously reported butanol production by wild-type Clostridium acetobutyl-icum ATCC 824 under similar conditions. Strain G117 also distinguishes itself by generating negligibleamount of ethanol, but producing butanol and acetone as biosolvent end-products. A butanol dehydro-genase gene (bdh gene) was identified in strain G117, which demonstrated a 200-fold increase in tran-scription level measured by quantitative real-time PCR after 10 h of culture growth. The hightranscription suggests that this bdh gene could be a putative gene involved in butanol production. Inall, Clostridium sp. strain G117 serves as a potential candidate for industrial biobutanol production whilethe absence of ethanol ensures an economic-efficient separation and purification of butanol. 2012 Elsevier Ltd. All rights reserved.