文献类型：期刊文献

英文题名：Pleiotropic regulation of a glucose-specific PTS in Clostridium acetobutylicum for high-efficient butanol production from corn stover without detoxification

作者：Wu, Youduo[1];Bai, Yidi[1];Zhang, Daojing[2];Cheng, Chi[1];Chen, Lijie[1];Bai, Fengwu[3];Xue, Chuang[1]

机构：[1]Dalian Univ Technol, Sch Bioengn, 2 Linggong Rd, Dalian 116024, Peoples R China;[2]East China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[3]Shanghai Jiao Tong Univ, Sch Life Sci & Biotechnol, Shanghai 200240, Peoples R China

年份：2019

卷号：12

期号：1

外文期刊名：BIOTECHNOLOGY FOR BIOFUELS

收录：;EI(收录号：20194707705923);WOS:【SCI-EXPANDED(收录号:WOS:000495590800001)】；

基金：This study was supported by the National Natural Science Foundation of China with Grant Numbers (21808027, 41861124004 & 21878035), the Open Funding Project of the State Key Laboratory of Bioreactor Engineering, the National Key R&D Program of China (2018YFB1501703), the Liaoning Revitalization Talents Program (XLYC1807269), the Dalian Science and Technology Innovation Project (2018J12SN074), the Liaoning Innovative Talent Support Program (LR2017005), the Youth Science and Technology Star Project of Dalian (2017RQ003), and the Fundamental Research Funds for the Central Universities (DUT17RC(4)006 & DUT19ZD213).

语种：英文

外文关键词：Clostridium acetobutylicum; Corn stover; PTS regulation; Inhibitor tolerance; Butanol productivity

摘要：Background Corn stover (CS) is evaluated as the most favorable candidate feedstock for butanol production via microbial acetone-butanol-ethanol (ABE) fermentation by Clostridium acetobutylicum. By independent acid pretreatment and enzymatic hydrolysis, fermentable sugars (mainly glucose and xylose) were released, of which glucose was naturally utilized as the most preferred carbon source by C. acetobutylicum. However, the ABE fermentation using corn stover hydrolysate (CSH) without detoxification is typically limited to poor sugars utilization, butanol production and productivity. In the presence of pretreatment-derived inhibitors, the intracellular ATP and NADH, as important factors involved in cell growth, solventogenesis initiation and stress response, are exceedingly challenged owing to disrupted glucose phosphotransferase system (PTS). Therefore, there is a necessity to develop effective engineering approaches to overcome these limitations for high-efficient butanol production from CSH without detoxification. Results PTS-engineered C. acetobutylicum strains were constructed via overexpression and knockout of gene glcG encoding glucose-specific PTS IICBA, which pleiotropically regulated glucose utilization, cell growth, solventogenesis and inhibitors tolerance. The PTSGlcG-overexpressing strain exhibited high fermentation efficiency, wherein butanol production and productivity was 11.1 g/L and 0.31 g/L/h, compared to those of 11.0 g/L and 0.15 g/L/h with the PTSGlcG-deficient strain. During CSH culture without detoxification, the PTSGlcG-overexpressing strain exhibited desirable inhibitors tolerance and solventogenesis with butanol production of 10.0 g/L, increased by 300% and 400% compared to those of 2.5 and 2.0 g/L with the control and PTSGlcG-deficient strains, respectively. As a result of extra glucose and 10 g/L CaCO3 addition into CSH, butanol production and productivity were further maximized to 12.5 g/L and 0.39 g/L/h. These validated improvements on the PTSGlcG-overexpressing strain were ascribed to not only efficient glucose transport but also its cascading effects on intracellular ATP and NADH generation, solventogenesis initiation and inhibitors tolerance at the exponential growth phase. Conclusion The PTSGluG regulation could be an effective engineering approach for high-efficient ABE fermentation from lignocellulosic hydrolysates without detoxification or wastewater generation, providing fundamental information for economically sustainable butanol production with high productivity.