6W6G

The Mycobacterium tuberculosis ClpB disaggregase hexamer structure in conformation I in the presence of DnaK chaperone and a model substrate

Summary for 6W6G

• Entry DOI: 10.2210/pdb6w6g/pdb
• EMDB information: 21553 21554 21555 21556 21557
• Descriptor: Chaperone protein ClpB, Substrate, PHOSPHOTHIOPHOSPHORIC ACID-ADENYLATE ESTER, ... (4 entities in total)
• Functional Keywords: clpb/dnak, protein aggregates, unfold, refold protein, chaperone
• Biological source: Mycobacterium tuberculosis; More
• Total number of polymer chains: 7
• Total formula weight: 565043.03

Authors

Yin, Y.,Li, H. (deposition date: 2020-03-16, release date: 2021-03-17, Last modification date: 2024-05-29)

Primary citation

Yin, Y.,Feng, X.,Yu, H.,Fay, A.,Kovach, A.,Glickman, M.S.,Li, H.
Structural basis for aggregate dissolution and refolding by the Mycobacterium tuberculosis ClpB-DnaK bi-chaperone system.
Cell Rep, 35:109166-109166, 2021

PubMed Abstract: The M. tuberculosis (Mtb) ClpB is a protein disaggregase that helps to rejuvenate the bacterial cell. DnaK is a protein foldase that can function alone, but it can also bind to the ClpB hexamer to physically couple protein disaggregation with protein refolding, although the molecular mechanism is not well understood. Here, we report the cryo-EM analysis of the Mtb ClpB-DnaK bi-chaperone in the presence of ATPγS and a protein substrate. We observe three ClpB conformations in the presence of DnaK, identify a conserved TGIP loop linking the oligonucleotide/oligosaccharide-binding domain and the nucleotide-binding domain that is important for ClpB function, derive the interface between the regulatory middle domain of the ClpB and the DnaK nucleotide-binding domain, and find that DnaK binding stabilizes, but does not bend or tilt, the ClpB middle domain. We propose a model for the synergistic actions of aggregate dissolution and refolding by the Mtb ClpB-DnaK bi-chaperone system.

PubMed: 34038719
DOI: 10.1016/j.celrep.2021.109166

Experimental method

ELECTRON MICROSCOPY (3.1 Å)