Driving Forces Enable High-Titer Anaerobic 1-Butanol Synthesis in Escherichia coli
Driving Forces Enable High-Titer Anaerobic 1-Butanol Synthesis in Escherichia coli
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DOI：
10.1128/aem.03034-10
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发表时间：
2011-05-01
影响因子：
4.4
通讯作者：
Liao, James C.
中科院分区：
文献类型：
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作者：
Shen, Claire R.;Lan, Ethan I.;Liao, James C.
1-丁醇是一种重要的化工原料和先进的生物燃料，由梭菌属物种产生。人们已经做出了各种努力来将梭菌1-丁醇途径转移到其他微生物中。然而，与类似化合物相比，仅获得有限滴度的1-丁醇。在这项工作中，我们在大肠杆菌中构建了一个修改的梭菌1-丁醇途径，以提供由反式烯酰辅酶A（CoA）还原酶（Ter）催化的不可逆反应，并产生NADH和乙酰辅酶A驱动力来引导通量。我们实现了高滴度（30克/升）和高产率（理论值的70至88%）的1-丁醇厌氧生产，相当于或超过了本地生产商所展示的水平。在没有NADH和乙酰辅酶A驱动力的情况下，单独的Ter反应仅达到约1/10的生产水平。工程化的宿主平台还能够选择具有更好催化效率或通过厌氧生长拯救表达的必需酶。这些结果证明了驱动力在有效生产非本地产品中的重要性。
1-Butanol, an important chemical feedstock and advanced biofuel, is produced by Clostridium species. Various efforts have been made to transfer the clostridial 1-butanol pathway into other microorganisms. However, in contrast to similar compounds, only limited titers of 1-butanol were attained. In this work, we constructed a modified clostridial 1-butanol pathway in Escherichia coli to provide an irreversible reaction catalyzed by trans-enoyl-coenzyme A (CoA) reductase (Ter) and created NADH and acetyl-CoA driving forces to direct the flux. We achieved high-titer (30 g/liter) and high-yield (70 to 88% of the theoretical) production of 1-butanol anaerobically, comparable to or exceeding the levels demonstrated by native producers. Without the NADH and acetyl-CoA driving forces, the Ter reaction alone only achieved about 1/10 the level of production. The engineered host platform also enables the selection of essential enzymes with better catalytic efficiency or expression by anaerobic growth rescue. These results demonstrate the importance of driving forces in the efficient production of nonnative products.