title: Crystal structure of a symmetric football-shaped GroEL:GroES2-ATP14 complex determined at 3.8Å reveals rearrangement between two GroEL rings.
abstract: The chaperonin GroEL is an essential chaperone that assists in protein folding with the aid of GroES and ATP. GroEL forms a double-ring structure, and both rings can bind GroES in the presence of ATP. Recent progress on the GroEL mechanism has revealed the importance of a symmetric 1:2 GroEL:GroES2 complex (the "football"-shaped complex) as a critical intermediate during the functional GroEL cycle. We determined the crystal structure of the football GroEL:GroES2-ATP14 complex from Escherichia coli at 3.8Å, using a GroEL mutant that is extremely defective in ATP hydrolysis. The overall structure of the football complex resembled the GroES-bound GroEL ring of the asymmetric 1:1 GroEL:GroES complex (the "bullet" complex). However, the two GroES-bound GroEL rings form a modified interface by an ~7° rotation about the 7-fold axis. As a result, the inter-ring contacts between the two GroEL rings in the football complex differed from those in the bullet complex. The differences provide a structural basis for the apparently impaired inter-ring negative cooperativity observed in several biochemical analyses.
authors.affiliation: Department of Applied Bioscience, Kanagawa Institute of Technology, 1030 Shimo-ogino, Atsugi, Kanagawa 243-0292, Japan.
authors.forename: Ayumi
authors.initials: A
authors.lastname: Koike-Takeshita
authors.affiliation: Department of Cell Biology, Graduate School of Medicine, Kyoto University, Yoshidakonoe-cho, Sakyo-Ku, Kyoto 606-8501, Japan.
authors.forename: Takatoshi
authors.initials: T
authors.lastname: Arakawa
authors.affiliation: Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, B-56, 4259 Nagatsuta, Midori-ku, Yokohama 226-8501, Japan. Electronic address: taguchi@bio.titech.ac.jp.
authors.forename: Hideki
authors.initials: H
authors.lastname: Taguchi
authors.affiliation: Department of Cell Biology, Graduate School of Medicine, Kyoto University, Yoshidakonoe-cho, Sakyo-Ku, Kyoto 606-8501, Japan; Membrane Protein Crystallography Project, Research Acceleration Program, Japan Science and Technology Agency, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan. Electronic address: t.shimamura@mfour.med.kyoto-u.ac.jp.
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Shimamura
mesh_terms: D000255:Adenosine Triphosphate / Q000737:chemistry*; D018835:Chaperonin 10 / Q000737:chemistry*; D018834:Chaperonin 60 / Q000737:chemistry*; D003460:Crystallization; D018360:Crystallography, X-Ray / Q000379:methods*; D004926:Escherichia coli / Q000737:chemistry*; D006868:Hydrolysis; D008958:Models, Molecular; D009154:Mutation; D036103:Nanotechnology; D011485:Protein Binding; D017510:Protein Folding; D017434:Protein Structure, Tertiary
chemical_list: D018835:Chaperonin 10; D018834:Chaperonin 60; D000255:Adenosine Triphosphate
keywords: chaperone; chaperonin; folding; inter-ring contacts; nanomachine