title: Global analysis of chaperone effects using a reconstituted cell-free translation system.
abstract: Protein folding is often hampered by protein aggregation, which can be prevented by a variety of chaperones in the cell. A dataset that evaluates which chaperones are effective for aggregation-prone proteins would provide an invaluable resource not only for understanding the roles of chaperones, but also for broader applications in protein science and engineering. Therefore, we comprehensively evaluated the effects of the major Escherichia coli chaperones, trigger factor, DnaK/DnaJ/GrpE, and GroEL/GroES, on ∼800 aggregation-prone cytosolic E. coli proteins, using a reconstituted chaperone-free translation system. Statistical analyses revealed the robustness and the intriguing properties of chaperones. The DnaK and GroEL systems drastically increased the solubilities of hundreds of proteins with weak biases, whereas trigger factor had only a marginal effect on solubility. The combined addition of the chaperones was effective for a subset of proteins that were not rescued by any single chaperone system, supporting the synergistic effect of these chaperones. The resource, which is accessible via a public database, can be used to investigate the properties of proteins of interest in terms of their solubilities and chaperone effects.
authors.affiliation: Department of Biomolecular Engineering, Graduate School of Biosciences and Biotechnology,  Tokyo Institute of Technology, Midori-ku, Yokohama 226-8501,  Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Niwa
authors.forename: Takashi
authors.initials: T
authors.lastname: Kanamori
authors.forename: Takuya
authors.initials: T
authors.lastname: Ueda
authors.forename: Hideki
authors.initials: H
authors.lastname: Taguchi
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D001665:Binding Sites / Q000235:genetics; D002474:Cell-Free System; D018835:Chaperonin 10 / Q000378:metabolism; D018834:Chaperonin 60 / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004926:Escherichia coli; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D050956:HSP40 Heat-Shock Proteins / Q000378:metabolism; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000378:metabolism; D018832:Molecular Chaperones / Q000378:metabolism*; D019696:Peptidylprolyl Isomerase / Q000378:metabolism; D017510:Protein Folding; D040901:Proteomics / Q000379:methods; D012044:Regression Analysis; D012995:Solubility
chemical_list: D001426:Bacterial Proteins; D018835:Chaperonin 10; D018834:Chaperonin 60; C494635:DnaJ protein, E coli; D029968:Escherichia coli Proteins; C489400:GrpE protein, E coli; D050956:HSP40 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; C063842:dnaK protein, E coli; C403324:trigger factor, E coli; D019696:Peptidylprolyl Isomerase