7R9K

Methanococcus maripaludis chaperonin, closed conformation 4

7R9K の概要

• エントリーDOI: 10.2210/pdb7r9k/pdb
• EMDBエントリー: 24324 24325 24326 24327 24328 24329 24330 24331
• 分子名称: Chaperonin (1 entity in total)
• 機能のキーワード: open conformation, chaperone
• 由来する生物種: Methanococcus maripaludis (Methanococcus deltae)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 54372.54

構造登録者

Zhao, Y.,Schmid, M.,Frydman, J.,Chiu, W. (登録日: 2021-06-29, 公開日: 2021-08-11, 最終更新日: 2024-06-05)

主引用文献

Zhao, Y.,Schmid, M.F.,Frydman, J.,Chiu, W.
CryoEM reveals the stochastic nature of individual ATP binding events in a group II chaperonin.
Nat Commun, 12:4754-4754, 2021

PubMed Abstract: Chaperonins are homo- or hetero-oligomeric complexes that use ATP binding and hydrolysis to facilitate protein folding. ATP hydrolysis exhibits both positive and negative cooperativity. The mechanism by which chaperonins coordinate ATP utilization in their multiple subunits remains unclear. Here we use cryoEM to study ATP binding in the homo-oligomeric archaeal chaperonin from Methanococcus maripaludis (MmCpn), consisting of two stacked rings composed of eight identical subunits each. Using a series of image classification steps, we obtained different structural snapshots of individual chaperonins undergoing the nucleotide binding process. We identified nucleotide-bound and free states of individual subunits in each chaperonin, allowing us to determine the ATP occupancy state of each MmCpn particle. We observe distinctive tertiary and quaternary structures reflecting variations in nucleotide occupancy and subunit conformations in each chaperonin complex. Detailed analysis of the nucleotide distribution in each MmCpn complex indicates that individual ATP binding events occur in a statistically random manner for MmCpn, both within and across the rings. Our findings illustrate the power of cryoEM to characterize a biochemical property of multi-subunit ligand binding cooperativity at the individual particle level.

PubMed: 34362932
DOI: 10.1038/s41467-021-25099-0

実験手法

ELECTRON MICROSCOPY (4.1 Å)