5OG1

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

Summary for 5OG1

• Entry DOI: 10.2210/pdb5og1/pdb
• Related: 5OFO
• EMDB information: 3776 3777
• Descriptor: Chaperone protein ClpB,ATP-dependent Clp protease ATP-binding subunit ClpA,Chaperone protein ClpB, PHOSPHOTHIOPHOSPHORIC ACID-ADENYLATE ESTER (2 entities in total)
• Functional Keywords: chaperone, disaggregase, clpb, aaa
• Biological source: Escherichia coli (strain K12); More
• Total number of polymer chains: 6
• Total formula weight: 587396.21

Authors

Deville, C.,Carroni, M.,Franke, K.B.,Topf, M.,Bukau, B.,Mogk, A.,Saibil, H.R. (deposition date: 2017-07-11, release date: 2017-08-16, Last modification date: 2024-05-08)

Primary citation

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

Experimental method

ELECTRON MICROSCOPY (4.5 Å)