Ionic-microenvironment stabilizes the disulfide engineered lysine decarboxylase for efficient cadaverine production  

作　　者：Zhuang Li Yaju Xue Xiuling Ji Yuhong Huang 

机构地区：[1]Beijing Key Laboratory of Ionic Liquids Clean Process,CAS Key Laboratory of Green Process and Engineering,State Key Laboratory of Multiphase Complex Systems,Institute of Process Engineering,Chinese Academy of Sciences,Beijing,100190,China [2]School of Chemical Engineering,University of Chinese Academy of Sciences,Beijing,100049,China [3]Innovation Academy for Green Manufacture,Chinese Academy of Sciences,Beijing,100190,China [4]Zhengzhou Institute of Emerging Industrial Technology,Zhengzhou,450000,China [5]Zhongke Langfang Institute of Process Engineering,Langfang,065001,China

出　　处：《Green Chemical Engineering》2023年第2期224-232,共9页绿色化学工程（英文）

基　　金：supported by the National Natural Science Foundation of China (grant number 22078346);Beijing Nova Program of Science and Technology (Z201100006820141);Innovation Academy for Green Manufacture, CAS (IAGM2020C19);Natural Science Foundation of Beijing (2204097);Henan Key Research and Development Project (202102210046);Hebei Provincial Natural Science Foundation (B2020103010);the CAS Pioneer Hundred Program。

摘　　要：Cadaverine is the key monomer for the synthesis of nylon 5X.Efficient and alkaline stable lysine decarboxylases are highly desirable for cadaverine production as the reaction pH increasing from 6.3 to 8.5.However,the most studied lysine decarboxylase CadA(E.coli)lost almost all activity at pH 8.0,which is the foremost challenge for the industrial-cadaverine production.In this study,we first found that the Na^(+)-microenvironment significantly improved the alkaline stability of the disulfide engineered lysine decarboxylaseΔLdcEt3(P233C/L628C)(half-life 362 h),compared to the conventional buffer(half-life 0.66 h)at pH 8.0.Meanwhile,the whole-cell conversion efficiency of the industrial-grade L-lysine withΔLdcEt3 could reach up to 99%in 2 h in the fermenter.Experi-mental investigation and molecular dynamics confirmed that Na^(+)-microenvironment could improve active-aggregation state and affect secondary structure ofΔLdcEt3.Therefore,Na^(+)-microenvironment stabilizesΔLdcEt3 providing a great potential industrial application for high-level cadaverine production.

关 键 词：Na^(+)-microenvironment Lysine decarboxylase ΔLdcEt3 Alkaline stability CADAVERINE 

分 类 号：TQ920.1[轻工技术与工程—发酵工程] TQ226.31