Ameliorating end-product inhibition to improve cadaverine production in engineered Escherichia coli and its application in the synthesis of bio-based diisocyanates  

作　　者：Xin Wang Xing Guo Jing Wang Hui Li Feng He Sheng Xu Kequan Chen Pingkai Ouyang 

机构地区：[1]State Key Laboratory of Materials-Oriented Chemical Engineering,College of Biotechnology and Pharmaceutical Engineering,Nanjing Tech University,Nanjing,211816,Jiangsu,China Bbitechnology and Bioengineering

出　　处：《Synthetic and Systems Biotechnology》2021年第4期243-253,共11页合成和系统生物技术（英文）

基　　金：This work is supported by the National Key R&D Program of China(2021YFC2100800);Key Research and Development Program(Social Development)Project of Jiangsu Province(BE2018730);the Jiangsu Synergetic Innovation Center for Advanced Bio-Manufacture(XTE1844 and XTB1806).

摘　　要：Cadaverine is an important C5 platform chemical with a wide range of industrial applications.However,the cadaverine inhibition on the fermenting strain limited its industrial efficiency of the strain.In this study,we report an engineered Escherichia coli strain with high cadaverine productivity that was generated by developing a robust host coupled with metabolic engineering to mitigate cadaverine inhibition.First,a lysine producing E.coli was treated with a combination of radiation(ultraviolet and visible spectrum)and ARTP(atmospheric and room temperature plasma)mutagenesis to obtain a robust host with high cadaverine tolerance.Three mutant targets including HokD,PhnI and PuuR are identified for improved cadaverine tolerance.Further transcriptome analysis suggested that cadaverine suppressed the synthesis of ATP and lysine precursor.Accordingly,the related genes involved in glycolysis and lysine precursor,as well as cadaverine exporter was engineered to release the cadaverine inhibition.The final engineered strain was fed-batch cultured and a titer of 58.7 g/L cadaverine was achieved with a yield of 0.396 g/g,both of which were the highest level reported to date in E.coli.The bio-based cadaverine was purified to>99.6%purity,and successfully used for the synthesis of polyurethane precursor 1,5-pentamethylene diisocyanate(PDI)through the approach of carbamate decomposition.

关 键 词：CADAVERINE End-product inhibition Escherichia coli Transcriptome analysis Metabolic engineering Bio-based diisocyanate 

分 类 号：O62[理学—有机化学]