1aon
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CRYSTAL STRUCTURE OF THE ASYMMETRIC CHAPERONIN COMPLEX GROEL/GROES/(ADP)7
OverviewOverview
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.
About this StructureAbout this Structure
1AON is a Protein complex structure of sequences from Escherichia coli with and as ligands. The following page contains interesting information on the relation of 1AON with [Chaperones]. Full crystallographic information is available from OCA.
ReferenceReference
The crystal structure of the asymmetric GroEL-GroES-(ADP)7 chaperonin complex., Xu Z, Horwich AL, Sigler PB, Nature. 1997 Aug 21;388(6644):741-50. PMID:9285585
Page seeded by OCA on Fri Feb 15 15:29:41 2008