Chaperonins GroEL and GroES collaborate in protein folding.
A set of cryo-EM structures of GroEL bound to ATP and computational modeling were used to trace the trajectory of sites that bind the substrate, an unfolded or misfolded polypeptide, from their initial positions lining the chaperonin ring through to formation of the folding chamber, which encapsulates but does not bind the substrate. The findings suggest ATP-powered domain twists that may enable the stretching and unfolding of the substrate prior to its release into the folding chamber.
From: Clare DK, Vasishtan D, Stagg S, Quispe J, Farr GW, Topf M, et al. ATP-Triggered Conformational Changes Delineate Substrate-Binding and -Folding Mechanics of the GroEL Chaperonin. Cell. 2012;149(1):113-23. Epub 2012/03/27. doi: 10.1016/j.cell.2012.02.047. PubMed PMID: 22445172.