title: Comparison of refolding activities between nanogel artificial chaperone and GroEL systems.
abstract: The chaperone-like activity of a nanogel of cholesteryl group-bearing pullulan (CHP) was compared with that of GroEL for refolding acid-denatured green fluorescent protein (GFP). The refolding of denatured GFP was carried out by dilution of acid-denatured GFP in the presence of the nanogel or GroEL. GFP fluorescence was increasingly repressed with increases in the concentration of the CHP nanogel or GroEL added to the dilution buffer. The concentrations of 50% inhibition of recovery of GFP fluorescence were 0.03 microM (GroEL) and 0.08 microM (CHP nanogel), respectively. The refolding was resumed by the addition of ATP into the GroEL (0.20 microM) system or by the addition of methyl-beta-cyclodextrin into the nanogel (0.20 microM) system. In the nanogel-GFP system, about 90% of the intensity was recovered within 10 min. The half time (t(1/2)) for refolding in the CHP nanogel system (36 s) is almost equal to that of the natural chaperone GroEL-GroES system.
authors.affiliation: Institute of Biomaterials & Bioengineering, Tokyo Medical & Dental University 2-3-10, Kanda-surugadai, Chiyoda-ku, Tokyo 101-0062, Japan.
authors.forename: Wakiko
authors.initials: W
authors.lastname: Asayama
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Sawada
authors.forename: Hideki
authors.initials: H
authors.lastname: Taguchi
authors.forename: Kazunari
authors.initials: K
authors.lastname: Akiyoshi
mesh_terms: D018835:Chaperonin 10 / Q000737:chemistry*; D018834:Chaperonin 60 / Q000737:chemistry*; D004926:Escherichia coli / Q000737:chemistry*; D029968:Escherichia coli Proteins / Q000737:chemistry*; D005782:Gels; D005936:Glucans / Q000737:chemistry*; D049452:Green Fluorescent Proteins / Q000737:chemistry*; D018832:Molecular Chaperones / Q000737:chemistry*; D017510:Protein Folding
chemical_list: D018835:Chaperonin 10; D018834:Chaperonin 60; D029968:Escherichia coli Proteins; D005782:Gels; D005936:Glucans; D018832:Molecular Chaperones; C485192:green fluorescent protein, Aequorea victoria; D049452:Green Fluorescent Proteins; C009109:pullulan