Enhanced 2,3-butanediol production from biodiesel-derived glycerol by engineering of cofactor regeneration and manipulating carbon flux in Bacillus amyloliquefaciens.
Enhanced 2,3-butanediol production from biodiesel-derived glycerol by engineering of cofactor regeneration and manipulating carbon flux in Bacillus amyloliquefaciens.
复制标题
通过辅因子再生工程和控制解淀粉芽孢杆菌中的碳通量提高生物柴油衍生甘油的 2,3-丁二醇产量
DOI：
10.1186/s12934-015-0317-2
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发表时间：
2015-08-22
影响因子：
6.4
通讯作者：
Yang ST
中科院分区：
文献类型：
--
作者：
Yang T;Rao Z;Zhang X;Xu M;Xu Z;Yang ST
背景：解淀粉芽孢杆菌 B10-127 在从生物柴油衍生的甘油中工业规模微生物发酵 2,3-丁二醇 (2,3-BD) 方面表现出优异的能力。然而，副产物（乙偶姻、乙偶姻、乳酸和琥珀酸盐）的积累和 2,3-BD 产量对于商业生产来说仍然过低。 结果：开发了几种策略来控制设计的解淀粉芽孢杆菌中 2,3-BD 分支的碳通量。首先，通过甘油脱氢酶和乙偶姻还原酶的共同过量生产，将额外拷贝的NADH/NAD(+)再生系统引入解淀粉芽孢杆菌中，从而提高2,3-BD的产量并抑制副产物的积累。随后，将中等启动子PbdhA控制下的转录调节因子ALsR引入解淀粉芽孢杆菌中，从而增加了2,3-BD分支的碳通量。最后，在分析2,3-BD发酵特性的基础上提出了三阶段溶解氧控制策略，并根据ACR对还原和氧化的不同pH偏好提出了两阶段pH控制策略。按照这些策略，获得了高滴度（102.3 g/L）、产量（0.44 g/g）和生产率（1.16 g/L/h）的2,3-BD。结论：据我们所知，这是使用生物柴油衍生的甘油作为底物报道的最高的2,3-BD生产，并且这种设计的解淀粉芽胞杆菌应该是工业规模生产2,3-BD的优秀候选者。
Background:Bacillus 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.Results:Several 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.Conclusions:To 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.