Novel switchable ECF sigma factor transcription system for improving thaxtomin A production in Streptomyces  

作　　者：Xuejin Zhao Weijia Wei Yeqing Zong Chaoxian Bai Xian Guo Hua Zhu Chunbo Lou 

机构地区：[1]State Key Laboratory of Microbial Resources,CAS Key Laboratory of Microbial Physiological and Metabolic Engineering,Institute of Microbiology,Chinese Academy of Sciences,Beijing,100101,China [2]CAS Key Laboratory of Pathogen Microbiology and Immunology,Institute of Microbiology,Chinese Academy of Sciences,Beijing,100101,China [3]Center for Cell and Gene Circuit Design,CAS Key Laboratory of Quantitative Engineering Biology,Guangdong Provincial Key Laboratory of Synthetic Genomics,Shenzhen Key Laboratory of Synthetic Genomics,Shenzhen Institute of Synthetic Biology,Shenzhen Institutes of Advanced Technology,Chinese Academy of Sciences,Shenzhen,518055,China [4]College of Life Sciences,University of Chinese Academy of Sciences,Beijing,100149,China

出　　处：《Synthetic and Systems Biotechnology》2022年第3期972-981,共10页合成和系统生物技术（英文）

基　　金：supported by the National Key Research and Development Program of China[2018YFA0900700];Natural Science Foundation of China[31900901 and 31500069];the Chinese Academy of Sciences[No.QYZDB-SSW-SMC050,No.XDPB1801 of the Strategic Priority Research Program];the Shenzhen Science and Technology Innovation Committee[No.JCYJ20180507182241844,JCHZ20200005,DWKF20190009].

摘　　要：The application of the valuable natural product thaxtomin A,a potent bioherbicide from the potato scab pathogenic Streptomyces strains,has been greatly hindered by the low yields from its native producers.Here,we developed an orthogonal transcription system,leveraging extra-cytoplasmic function(ECF)sigma(σ)factor 17(ECF17)and its cognate promoter Pecf17,to express the thaxtomin gene cluster and improve the production of thaxtomin A.The minimal Pecf17 promoter was determined,and a Pecf17 promoter library with a wide range of strengths was constructed.Furthermore,a cumate inducible system was developed for precise temporal control of the ECF17 transcription system in S.venezuelae ISP5230.Theoretically,the switchable ECF17 transcription system could reduce the unwanted influences from host and alleviate the burdens introduced by overexpression of heterologous genes.The yield of thaxtomin A was significantly improved to 202.1±15.3μg/mL using the switchable ECF17 transcription system for heterologous expression of the thaxtomin gene cluster in S.venezuelae ISP5230.Besides,the applicability of this transcription system was also tested in Streptomyces albus J1074,and the titer of thaxtomin A was raised to as high as 239.3±30.6μg/mL.Therefore,the inducible ECF17 transcription system could serve as a complement of the generally used transcription systems based on strong native constitutive promoters and housekeepingσfactors for the heterologous expression of valuable products in diverse Streptomyces hosts.

关 键 词：STREPTOMYCES ECF17 sigma factor Heterologous expression Thaxtomin A Transcription system 

分 类 号：Q939[生物学—微生物学]