School of Bioengineering, Dalian University of Technology, Dalian, 116024, China.
Department of Chemical and Biomolecular Engineering, The Ohio State University, 151 West Woodruff Avenue, Columbus, OH, 43210, USA.
Appl Microbiol Biotechnol. 2019 Jul;103(14):5549-5566. doi: 10.1007/s00253-019-09916-7. Epub 2019 May 29.
Clostridia are Gram-positive, spore-forming, obligate anaerobic bacteria that can produce solvents such as acetone, ethanol, and butanol, which can be used as biofuels or building block chemicals. Many successful attempts have been made to improve solvent yield and titer from sugars through metabolic engineering of solventogenic and acidogenic clostridia. More recently, cellulolytic and acetogenic clostridia have also attracted high interests for their ability to utilize low-cost renewable substrates such as cellulose and syngas. Process engineering such as in situ butanol recovery and consolidated bioprocessing (CBP) has been developed for improved solvent titer and productivity. This review focuses on metabolic and process engineering strategies for solvent production from sugars, lignocellulosic biomass, and syngas by various clostridia, including conventional solventogenic Clostridium acetobutylicum, engineered acidogens such as C. tyrobutyricum and C. cellulovorans, and carboxydotrophic acetogens such as C. carboxidivorans and C. ljungdahlii.
梭菌是革兰氏阳性、产芽孢、严格厌氧的细菌，能够产生丙酮、乙醇和丁醇等溶剂，可作为生物燃料或基础化工原料。通过对产溶剂梭菌和产酸梭菌的代谢工程改造，已经成功地尝试了许多方法来提高糖基溶剂的产量和效价。最近，由于能够利用纤维素和合成气等低成本可再生底物，纤维分解梭菌和乙酰生成梭菌也引起了人们的高度关注。为了提高溶剂效价和生产力，已经开发了原位丁醇回收和整合生物加工（CBP）等工艺工程技术。本文重点综述了利用各种梭菌（包括传统产溶剂梭菌丙酮丁醇梭菌、工程化产酸梭菌如酪丁酸梭菌和纤维梭菌以及羧化营养型乙酰生成梭菌如醋杆菌和巨形梭菌）从糖、木质纤维素生物质和合成气生产溶剂的代谢和工艺工程策略。
