title: Iteratively improving natamycin production in Streptomyces gilvosporeus by a large operon-reporter based strategy.
abstract: Many high-value secondary metabolites are assembled by very large multifunctional polyketide synthases or non-ribosomal peptide synthetases encoded by giant genes, for instance, natamycin production in an industrial strain of Streptomyces gilvosporeus. In this study, a large operon reporter-based selection system has been developed using the selectable marker gene neo to report the expression both of the large polyketide synthase genes and of the entire gene cluster, thereby facilitating the selection of natamycin-overproducing mutants by iterative random mutagenesis breeding. In three successive rounds of mutagenesis and selection, the natamycin titer was increased by 110%, 230%, and 340%, respectively, and the expression of the whole biosynthetic gene cluster was correspondingly increased. An additional copy of the natamycin gene cluster was found in one overproducer. These findings support the large operon reporter-based selection system as a useful tool for the improvement of industrial strains utilized in the production of polyketides and non-ribosomal peptides.
authors.affiliation: State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200030, China.
authors.forename: Yemin
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200030, China.
authors.forename: Zhengsheng
authors.initials: Z
authors.lastname: Tao
authors.affiliation: State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200030, China.
authors.forename: Hualiang
authors.initials: H
authors.lastname: Zheng
authors.affiliation: State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200030, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200030, China.
authors.forename: Qingshan
authors.initials: Q
authors.lastname: Long
authors.affiliation: State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200030, China.
authors.forename: Zixin
authors.initials: Z
authors.lastname: Deng
authors.affiliation: State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200030, China. Electronic address: tao_meifeng@sjtu.edu.cn.
authors.forename: Meifeng
authors.initials: M
authors.lastname: Tao
mesh_terms: D053898:Biosynthetic Pathways / Q000235:genetics; D020869:Gene Expression Profiling / Q000379:methods; D017930:Genes, Reporter / Q000235:genetics*; D024861:Genetic Enhancement / Q000379:methods*; D060847:Metabolic Engineering / Q000379:methods*; D064688:Metabolic Flux Analysis / Q000379:methods; D053858:Metabolic Networks and Pathways / Q000235:genetics; D005810:Multigene Family / Q000235:genetics; D010866:Natamycin / Q000096:biosynthesis* / Q000302:isolation & purification; D009876:Operon / Q000235:genetics*; D048630:Polyketide Synthases / Q000235:genetics*; D013045:Species Specificity; D013302:Streptomyces / Q000145:classification / Q000502:physiology*
chemical_list: D048630:Polyketide Synthases; D010866:Natamycin
keywords: Large genes; Natamycin; Non-ribosomal peptide synthetase; Polyketide synthase; Reporter; Strain improvement