4AAS

ATP-triggered molecular mechanics of the chaperonin GroEL

Summary for 4AAS

• Entry DOI: 10.2210/pdb4aas/pdb
• Related: 4AAQ 4AAR 4AAU 4AB2 4AB3
• EMDB information: 2000
• Descriptor: 60 KDA CHAPERONIN, PHOSPHATE ION, MAGNESIUM ION, ... (4 entities in total)
• Functional Keywords: chaperone
• Biological source: ESCHERICHIA COLI
• Cellular location: Cytoplasm : P0A6F5
• Total number of polymer chains: 14
• Total formula weight: 807253.04

Authors

Clare, D.K.,Vasishtan, D.,Stagg, S.,Quispe, J.,Farr, G.W.,Topf, M.,Horwich, A.L.,Saibil, H.R. (deposition date: 2011-12-05, release date: 2012-12-12, Last modification date: 2024-05-08)

Primary citation

Clare, D.K.,Vasishtan, D.,Stagg, S.,Quispe, J.,Farr, G.W.,Topf, M.,Horwich, A.L.,Saibil, H.R.
ATP-Triggered Conformational Changes Delineate Substrate-Binding and -Folding Mechanics of the Groel Chaperonin.
Cell(Cambridge,Mass.), 149:113-, 2012

PubMed Abstract: The chaperonin GroEL assists the folding of nascent or stress-denatured polypeptides by actions of binding and encapsulation. ATP binding initiates a series of conformational changes triggering the association of the cochaperonin GroES, followed by further large movements that eject the substrate polypeptide from hydrophobic binding sites into a GroES-capped, hydrophilic folding chamber. We used cryo-electron microscopy, statistical analysis, and flexible fitting to resolve a set of distinct GroEL-ATP conformations that can be ordered into a trajectory of domain rotation and elevation. The initial conformations are likely to be the ones that capture polypeptide substrate. Then the binding domains extend radially to separate from each other but maintain their binding surfaces facing the cavity, potentially exerting mechanical force upon kinetically trapped, misfolded substrates. The extended conformation also provides a potential docking site for GroES, to trigger the final, 100° domain rotation constituting the "power stroke" that ejects substrate into the folding chamber.

PubMed: 22445172
DOI: 10.1016/J.CELL.2012.02.047

Experimental method

ELECTRON MICROSCOPY (8.5 Å)