title: Production of novel antibiotics zeamines through optimizing Dickeya zeae fermentation conditions.
abstract: Dickeya zeae strain EC1 was recently shown to produce a new type of phytotoxins designated as zeamine and zeamine II, which are potent wide-spectrum antibiotics against Gram-positive and Gram-negative bacterial pathogens, suggesting their promising potential as clinical medicines. In this study, the optimized medium composition and culture conditions for biosynthesis of novel antibiotics zeamines have been established by using response surface methodology, largely increasing the yield of zeamines from original about 7.35 µg · mL(-1) in minimal medium to about 150 µg · mL(-1) in LS5 medium. The study identified the major factors contributing to zeamines production, which include nitrate, sucrose, asparaginate, mineral elements Mg2+ and K+, and optimized amount of phosphate. In addition, the results showed that overexpression of zmsK in D. zeae strain EC1 could further increase zeamines yield to about 180 µg · mL(-1) in LS5 medium. The findings from this study could facilitate further characterization and utilization of these two novel antibiotics, and also provide useful clues for understanding the regulatory mechanisms that govern D. zeae virulence.
authors.affiliation: Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Peoples' Republic of China.
authors.forename: Lisheng
authors.initials: L
authors.lastname: Liao
authors.affiliation: Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Peoples' Republic of China.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Cheng
authors.affiliation: Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Peoples' Republic of China.
authors.forename: Shiyin
authors.initials: S
authors.lastname: Liu
authors.affiliation: Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Peoples' Republic of China.
authors.forename: Jianuan
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore, Republic of Singapore.
authors.forename: Shuwen
authors.initials: S
authors.lastname: An
authors.affiliation: Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Peoples' Republic of China.
authors.forename: Mingfa
authors.initials: M
authors.lastname: Lv
authors.affiliation: Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Peoples' Republic of China.
authors.forename: Yufan
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Peoples' Republic of China.
authors.forename: Yanfang
authors.initials: Y
authors.lastname: Gu
authors.affiliation: Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Peoples' Republic of China.
authors.forename: Shaohua
authors.initials: S
authors.lastname: Chen
authors.affiliation: Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Peoples' Republic of China; Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore, Republic of Singapore; Department of Biological Sciences, National University of Singapore, Singapore, Republic of Singapore.
authors.forename: Lian-Hui
authors.initials: LH
authors.lastname: Zhang
mesh_terms: D000900:Anti-Bacterial Agents / Q000378:metabolism*; D018929:Cell Culture Techniques; D004755:Enterobacteriaceae / Q000378:metabolism*; D005285:Fermentation; D007218:Industrial Microbiology; D018942:Macrolides / Q000378:metabolism*; D011073:Polyamines / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D018942:Macrolides; D011073:Polyamines; C547236:zeamine