It has been widely believed that an asymmetric GroEL-GroES complex (termed the bullet-shaped complex) is formed solely throughout the chaperonin reaction cycle, whereas we have recently revealed that a symmetric GroEL-(GroES)(2) complex (the football-shaped complex) can form in the presence of denatured proteins. However, the dynamics of the GroEL-GroES interaction, including the football-shaped complex, is unclear. We investigated the decay process of the football-shaped complex at a single-molecule level. Because submicromolar concentrations of fluorescent GroES are required in solution to form saturated amounts of the football-shaped complex, single-molecule fluorescence imaging was carried out using zero-mode waveguides. The single-molecule study revealed two insights into the GroEL-GroES reaction. First, the first GroES to interact with GroEL does not always dissociate from the football-shaped complex prior to the dissociation of a second GroES. Second, there are two cycles, the "football cycle " and the "bullet cycle," in the chaperonin reaction, and the lifetimes of the football-shaped and the bullet-shaped complexes were determined to be 3-5 s and about 6 s, respectively. These findings shed new light on the molecular mechanism of protein folding mediated by the GroEL-GroES chaperonin system.
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http://dx.doi.org/10.1074/jbc.M110.122101 | DOI Listing |
Acc Chem Res
June 2024
MOE Key Laboratory for Non-Equilibrium Synthesis and Modulation of Condensed Matter, School of Physics, Xi'an Jiaotong University, Xi'an, 710049 Shaanxi, China.
ConspectusBuckminsterfullerene, C, was discovered through a prominent mass peak containing 60 atoms produced from laser vaporization of graphite, driven by Kroto's interest in understanding the formation mechanisms of carbon-containing molecules in space. Inspired by the geodesic dome-shaped architecture designed by Richard Buckminster Fuller, after whom the particle was named, C was found to have a football-shaped structure comprising 20 hexagons and 12 pentagons. It sparked worldwide interest in understanding this new carbon allotrope, resulting in the awarding of the Noble Prize in Chemistry to Smalley, Kroto, and Curl in 1996.
View Article and Find Full Text PDFStructure
June 2024
Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo City, Tokyo 113-8654, Japan; Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Bunkyo City, Tokyo 113-8654, Japan. Electronic address:
Group I chaperonins are dual heptamer protein complexes that play significant roles in protein homeostasis. The structure and function of the Escherichia coli chaperonin are well characterized. However, the dynamic properties of chaperonins, such as large ATPase-dependent conformational changes by binding of lid-like co-chaperonin GroES, have made structural analyses challenging, and our understanding of these changes during the turnover of chaperonin complex formation is limited.
View Article and Find Full Text PDFiScience
January 2022
School of Biology, Institute of Molecular Biology and Genetics, Seoul National University, Seoul 08826, Republic of Korea.
Microscopy (Oxf)
June 2021
Department of Applied Chemistry and Bioscience, Graduate School of Engineering, Kanagawa Institute of Technology, 1030 Shimo-ogino, Atsugi, Kanagawa 243-0292, Japan.
Escherichia coli chaperonin GroEL, which is a large cylindrical protein complex comprising two heptameric rings with cavities of 4.5 nm each in the center, assists in intracellular protein folding with the aid of GroES and adenosine triphosphate (ATP). Here, we investigated the possibility that GroEL can also encapsulate metal nanoparticles (NPs) up to ∼5 nm in diameter into the cavities with the aid of GroES and ATP.
View Article and Find Full Text PDFJ Biol Chem
September 2019
Department of Structural Biology, Weizmann Institute of Science, Rehovot 7610001, Israel
The chaperonin GroEL and its co-chaperonin GroES form both GroEL-GroES bullet-shaped and GroEL-GroES football-shaped complexes. The residence time of protein substrates in the cavities of these complexes is about 10 and 1 s, respectively. There has been much controversy regarding which of these complexes is the main functional form.
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