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X-Ray Crystallography to Study the Oligomeric State Transition of the Thermotoga maritima M42 Aminopeptidase TmPep1050
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A proteolytic AAA+ machine poised to unfold a protein substrate
Alireza Ghanbarpour1, Robert T Sauer1, Joseph H Davis1,2
1Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139.
Biorxiv : the Preprint Server for Biology
|January 3, 2024
Summary
AAA+ proteases like ClpXP unfold proteins for degradation. Cryo-electron microscopy (cryo-EM) visualized a novel intermediate state during substrate unfolding and degradation by ClpXP.
Area of Science:
- Molecular Biology
- Protein Degradation
- Structural Biology
Background:
- AAA+ proteins are molecular machines that utilize ATP hydrolysis to perform mechanical work.
- Protein degradation is a crucial cellular process regulated by proteases.
- The ClpXP protease complex plays a vital role in degrading misfolded or damaged proteins.
Conclusions:
- The study reveals a key intermediate in ClpXP-mediated protein unfolding and degradation.
- Structural insights demonstrate how ClpXP initiates unfolding by tightly gripping the substrate.
- Conformational flexibility within the ClpX hexamer is critical for substrate processing.
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