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-Structure paper
Title | The crystal structure of the asymmetric GroEL-GroES-(ADP)7 chaperonin complex. |
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Journal, issue, pages | Nature, Vol. 388, Issue 6644, Page 741-750, Year 1997 |
Publish date | Aug 21, 1997 |
Authors | Z Xu / A L Horwich / P B Sigler / |
PubMed Abstract | Chaperonins assist protein folding with the consumption of ATP. They exist as multi-subunit protein assemblies comprising rings of subunits stacked back to back. In Escherichia coli, asymmetric ...Chaperonins assist protein folding with the consumption of ATP. They exist as multi-subunit protein assemblies comprising rings of subunits stacked back to back. In Escherichia coli, asymmetric intermediates of GroEL are formed with the co-chaperonin GroES and nucleotides bound only to one of the seven-subunit rings (the cis ring) and not to the opposing ring (the trans ring). The structure of the GroEL-GroES-(ADP)7 complex reveals how large en bloc movements of the cis ring's intermediate and apical domains enable bound GroES to stabilize a folding chamber with ADP confined to the cis ring. Elevation and twist of the apical domains double the volume of the central cavity and bury hydrophobic peptide-binding residues in the interface with GroES, as well as between GroEL subunits, leaving a hydrophilic cavity lining that is conducive to protein folding. An inward tilt of the cis equatorial domain causes an outward tilt in the trans ring that opposes the binding of a second GroES. When combined with new functional results, this negative allosteric mechanism suggests a model for an ATP-driven folding cycle that requires a double toroid. |
External links | Nature / PubMed:9285585 |
Methods | X-ray diffraction |
Resolution | 3 Å |
Structure data | PDB-1aon: |
Chemicals | ChemComp-MG: ChemComp-ADP: |
Source |
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Keywords | COMPLEX (GROEL/GROES) / COMPLEX (GROEL-GROES) / CHAPERONIN ASSISTED PROTEIN FOLDING / COMPLEX (GROEL-GROES) complex |