title: Genome-scale metabolic network reconstruction of Saccharopolyspora spinosa for spinosad production improvement.
abstract: BACKGROUND
  Spinosad is a macrolide antibiotic produced by Saccharopolyspora spinosa with aerobic fermentation. However, the wild strain has a low productivity. In this article, a computational guided engineering approach was adopted in order to improve the yield of spinosad in S. spinosa.
  
  
  RESULTS
  Firstly, a genome-scale metabolic network reconstruction (GSMR) for S.spinosa based on its genome information, literature data and experimental data was established. The model was consists of 1,577 reactions, 1,726 metabolites, and 733 enzymes after manually refined. Then, amino acids supplying experiments were performed in order to test the capabilities of the model, and the results showed a high consistency. Subsequently, transhydrogenase (PntAB, EC 1.6.1.2) was chosen as the potential target for spinosad yield improvement based on the in silico metabolic network models. Furthermore, the target gene was manipulated in the parent strain in order to validate the model predictions. At last, shake flask fermentation was carried out which led to spinosad production of 75.32 mg/L, 86.5% higher than the parent strain (40.39 mg/L).
  
  
  CONCLUSIONS
  Results confirmed the model had a high potential in engineering S. spinosa for spinosad production. It is the first GSMM for S.spinosa, it has significance for a better understanding of the comprehensive metabolism and guiding strain designing of Saccharopolyspora spinosa in the future.
authors.forename: Xiaoyang
authors.initials: X
authors.lastname: Wang
authors.forename: Chuanbo
authors.initials: C
authors.lastname: Zhang
authors.forename: Meiling
authors.initials: M
authors.lastname: Wang
authors.affiliation: Department of Biological Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China. wenyulu@tju.edu.cn.
authors.forename: Wenyu
authors.initials: W
authors.lastname: Lu
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D018533:Biomass; D004338:Drug Combinations; D016680:Genome, Bacterial; D018942:Macrolides / Q000378:metabolism*; D060847:Metabolic Engineering; D053858:Metabolic Networks and Pathways / Q000235:genetics; D016930:Saccharopolyspora / Q000235:genetics / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D001426:Bacterial Proteins; D004338:Drug Combinations; D018942:Macrolides; C415329:spinosad