1pcq

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spinqualitylabelsall models 1pcq, resolution 2.808Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

Crystal structure of groEL-groES

Overview

Productive cis folding by the chaperonin GroEL is triggered by the binding, of ATP but not ADP, along with cochaperonin GroES, to the same ring as, non-native polypeptide, ejecting polypeptide into an encapsulated, hydrophilic chamber. We examined the specific contribution of the, gamma-phosphate of ATP to this activation process using complexes of ADP, and aluminium or beryllium fluoride. These ATP analogues supported, productive cis folding of the substrate protein, rhodanese, even when, added to already-formed, folding-inactive cis ADP ternary complexes, essentially introducing the gamma-phosphate of ATP in an independent step., Aluminium fluoride was observed to stabilize the association of GroES with, GroEL, with a substantial release of free energy (-46 kcal/mol). To, understand the basis of such activation and stabilization, a crystal, structure of GroEL-GroES-ADP.AlF3 was determined at 2.8 A. A trigonal AlF3, metal complex was observed in the gamma-phosphate position of the, nucleotide pocket of the cis ring. Surprisingly, when this structure was, compared with that of the previously determined GroEL-GroES-ADP complex, no other differences were observed. We discuss the likely basis of the, ability of gamma-phosphate binding to convert preformed, GroEL-GroES-ADP-polypeptide complexes into the folding-active state.

About this Structure

1PCQ is a Protein complex structure of sequences from Escherichia coli with MG, K, ADP and AF3 as ligands. Full crystallographic information is available from OCA.

Reference

Role of the gamma-phosphate of ATP in triggering protein folding by GroEL-GroES: function, structure and energetics., Chaudhry C, Farr GW, Todd MJ, Rye HS, Brunger AT, Adams PD, Horwich AL, Sigler PB, EMBO J. 2003 Oct 1;22(19):4877-87. PMID:14517228

Page seeded by OCA on Tue Nov 20 23:41:39 2007