5OFO

Cryo EM structure of the E. coli disaggregase ClpB (BAP form, DWB mutant), in the ATPgammaS state, bound to the model substrate casein

5OFO の概要

• エントリーDOI: 10.2210/pdb5ofo/pdb
• 関連するPDBエントリー: 5OG1
• EMDBエントリー: 3776 3777
• 分子名称: Chaperone protein ClpB,ATP-dependent Clp protease ATP-binding subunit ClpA,Chaperone protein ClpB, PHOSPHOTHIOPHOSPHORIC ACID-ADENYLATE ESTER (2 entities in total)
• 機能のキーワード: chaperone, disaggregase, clpb, aaa
• 由来する生物種: Escherichia coli (strain K12); 詳細
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 589489.20

構造登録者

Deville, C.,Carroni, M.,Franke, K.B.,Topf, M.,Bukau, B.,Mogk, A.,Saibil, H.R. (登録日: 2017-07-11, 公開日: 2017-08-16, 最終更新日: 2024-05-08)

主引用文献

Deville, C.,Carroni, M.,Franke, K.B.,Topf, M.,Bukau, B.,Mogk, A.,Saibil, H.R.
Structural pathway of regulated substrate transfer and threading through an Hsp100 disaggregase.
Sci Adv, 3:e1701726-e1701726, 2017

PubMed Abstract: Refolding aggregated proteins is essential in combating cellular proteotoxic stress. Together with Hsp70, Hsp100 chaperones, including ClpB, form a powerful disaggregation machine that threads aggregated polypeptides through the central pore of tandem adenosine triphosphatase (ATPase) rings. To visualize protein disaggregation, we determined cryo-electron microscopy structures of inactive and substrate-bound ClpB in the presence of adenosine 5'--(3-thiotriphosphate), revealing closed AAA+ rings with a pronounced seam. In the substrate-free state, a marked gradient of resolution, likely corresponding to mobility, spans across the AAA+ rings with a dynamic hotspot at the seam. On the seam side, the coiled-coil regulatory domains are locked in a horizontal, inactive orientation. On the opposite side, the regulatory domains are accessible for Hsp70 binding, substrate targeting, and activation. In the presence of the model substrate casein, the polypeptide threads through the entire pore channel and increased nucleotide occupancy correlates with higher ATPase activity. Substrate-induced domain displacements indicate a pathway of regulated substrate transfer from Hsp70 to the ClpB pore, inside which a spiral of loops contacts the substrate. The seam pore loops undergo marked displacements, along with ordering of the regulatory domains. These asymmetric movements suggest a mechanism for ATPase activation and substrate threading during disaggregation.

PubMed: 28798962
DOI: 10.1126/sciadv.1701726

実験手法

ELECTRON MICROSCOPY (4.6 Å)