3J03

Lidless Mm-cpn in the closed state with ATP/AlFx

Summary for 3J03

• Entry DOI: 10.2210/pdb3j03/pdb
• Related: 3J02
• EMDB information: 5138
• Descriptor: Lidless Mm-cpn (1 entity in total)
• Functional Keywords: group ii chaperonin, protein folding, mm-cpn, single particle reconstruction, methanococcus maripaludis, chaperone
• Biological source: Methanococcus maripaludis
• Total number of polymer chains: 16
• Total formula weight: 841896.56

Authors

Zhang, J.,Ma, B.,DiMaio, F.,Douglas, N.R.,Joachimiak, L.,Baker, D.,Frydman, J.,Levitt, M.,Chiu, W. (deposition date: 2011-02-10, release date: 2011-05-18, Last modification date: 2024-02-21)

Primary citation

Zhang, J.,Ma, B.,DiMaio, F.,Douglas, N.R.,Joachimiak, L.A.,Baker, D.,Frydman, J.,Levitt, M.,Chiu, W.
Cryo-EM structure of a group II chaperonin in the prehydrolysis ATP-bound state leading to lid closure.
Structure, 19:633-639, 2011

PubMed Abstract: Chaperonins are large ATP-driven molecular machines that mediate cellular protein folding. Group II chaperonins use their "built-in lid" to close their central folding chamber. Here we report the structure of an archaeal group II chaperonin in its prehydrolysis ATP-bound state at subnanometer resolution using single particle cryo-electron microscopy (cryo-EM). Structural comparison of Mm-cpn in ATP-free, ATP-bound, and ATP-hydrolysis states reveals that ATP binding alone causes the chaperonin to close slightly with a ∼45° counterclockwise rotation of the apical domain. The subsequent ATP hydrolysis drives each subunit to rock toward the folding chamber and to close the lid completely. These motions are attributable to the local interactions of specific active site residues with the nucleotide, the tight couplings between the apical and intermediate domains within the subunit, and the aligned interactions between two subunits across the rings. This mechanism of structural changes in response to ATP is entirely different from those found in group I chaperonins.

PubMed: 21565698
DOI: 10.1016/j.str.2011.03.005

Experimental method

ELECTRON MICROSCOPY (4.8 Å)