基于产溶剂梭菌的NAD(P)H补偿模块对中心碳代谢的调控作用研究

Cofactor can be a powerful tool to achieve some industrial objectives. In solventogenic clostridia, a large quantity of oxidation products, especially acetone and CO2 are produced due to the deficiency of reducing equivalents NAD(P)H in central carbon metabolism, which leads to a low atomy economy. Although the importance of NAD(P)H to eliminate acetone and improve atom economy has been long recognized, there are no effective constructs that can be employed to effectively enhance NAD(P)H at present. Here, based on our previous discovery, we creatively construct an NAD(P)H-compensating module to manipulate the supply of NAD(P)H. For the first time, acetone can be perfectly removed without scarifying butanol and the atomy economy is dramatically improved. In the present study, systematic manipulation of NAD(P)H supply and their types (NADH or NADPH) will be carried out, and the adaption of clostridia metabolism to the change of NAD(P)H will be studied, in term of gene transcription, protein biosynthesis, and metabolic activity and so on. This study will provide important insights into the regulation of metabolism by NAD(P)H in solventogenic clostridia, and serve as a model design for improving the atom economies of bioprocesses performed by solventogenic clostridia, with novel perspectives and scientific basis.

辅因子可以为实现特定工业技术目标提供一个强大的工具。产溶剂梭菌中心碳代谢过程因还原力的丢失导致大量氧化态副产物丙酮和CO2的生成，严重影响了底物转化的原子经济性。尽管NAD(P)H在消除丙酮形成、提升原子经济性方面的重要作用已得到人们的认识，然而目前在NAD(P)H强化供给方面尚无有效的工程构建。基于前期发现，申请人创新地通过NAD(P)H补偿模块的构建，能够有效地调控NAD(P)H供给过程，实现丙酮的彻底消除（至可忽略的水平），不牺牲丁醇又能大幅度地提高总溶剂得率。研究将进一步开展补偿模块在NAD(P)H供给能力、辅酶类型等方面的控制，阐明细胞在基因转录、关键蛋白合成以及产物代谢等层次上的响应，从而系统揭示NAD(P)H对产溶剂梭菌中心碳代谢的调控作用，为提升产溶剂梭菌底物转化过程原子经济性的研究提供新的思路、范例与理论依据。

辅因子可以为实现特定工业技术目标提供一个强大的工具。产溶剂梭菌中心碳代谢过程因还原力的丢失导致大量氧化态副产物丙酮和CO2的生成，严重影响了底物转化的原子经济性。尽管NAD(P)H在消除丙酮形成、提升原子经济性方面的重要作用已得到人们的认识，然而在NAD(P)H强化供给方面尚无有效的工程构建。在本项目中，申请人通过NAD(P)H补偿模块的构建，能够有效地调控NAD(P)H供给过程，实现丙酮的彻底消除，不牺牲丁醇又能大幅度地提高总溶剂得率。研究还阐明了还原力补偿条件下，细胞在基因转录、关键蛋白合成以及产物代谢等层次上的响应，从而系统揭示了NAD(P)H对产溶剂梭菌中心碳代谢的调控作用，为提升产溶剂梭菌底物转化过程原子经济性的研究提供新的思路、范例与理论依据。