Enhanced 2,3-butanediol production from biodiesel-derived glycerol by engineering of cofactor regeneration and manipulating carbon flux in Bacillus amyloliquefaciens

Microbial Cell Factories

Research

Shang-Tian Yang¹  Zhenghong Xu²  Taowei Yang³  Meijuan Xu³  Xian Zhang³  Zhiming Rao⁴ 

[1] Department of Chemical and Biomolecular Engineering, The Ohio State University, 43210, Columbus, OH, USA;Laboratory of Pharmaceutical Engineering, School of Pharmaceutical Science, Jiangnan University, 214122, Wuxi, Jiangsu Province, China;The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 214122, Wuxi, Jiangsu Province, China;The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 214122, Wuxi, Jiangsu Province, China;School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, 214122, Wuxi, Jiangsu, China;

关键词: 2,3-butanediol;    Glycerol;    Cofactor regeneration;    Manipulating carbon flux;    Bacillus amyloliquefaciens;   

DOI  :  10.1186/s12934-015-0317-2

 received in 2015-06-28, accepted in 2015-08-12,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundBacillus amyloliquefaciens B10-127 exhibited an excellent ability for industrial-scale microbial fermentation of 2,3-butanediol (2,3-BD) from biodiesel-derived glycerol. However, the accumulation of by-products (acetoin, acetoin, lactate and succinate) and the 2,3-BD yield remains prohibitively low for commercial production.ResultsSeveral strategies were developed to manipulate the carbon flux to 2,3-BD branch in a designed B. amyloliquefaciens. Firstly, extra copies of NADH/NAD+ regeneration system were introduced into B. amyloliquefaciens by co-overproduction of glycerol dehydrogenase and acetoin reductase, which resulting in improvement of 2,3-BD production and suppression of by-products accumulation. Subsequently, the transcriptional regulator ALsR under the control of a moderate promoter PbdhA was introduced into B. amyloliquefaciens, which increased carbon flux to 2,3-BD branch. Finally, a three-stage dissolved oxygen control strategy were proposed based on analysis of the characteristic of 2,3-BD fermentation, and a two-stage pH control strategy were proposed based on different pH preferences of ACR for reduction and oxidation. Following these strategies, a high titer (102.3 g/L), yield (0.44 g/g), and productivity (1.16 g/L/h) of 2,3-BD were achieved.ConclusionsTo our knowledge, this is the highest reported 2,3-BD production using biodiesel-derived glycerol as substrate, and this designed B. amyloliquefaciens should be an excellent candidate for producing 2,3-BD on an industrial scale.

【 授权许可】

CC BY   
© Yang et al. 2015