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Updated: Jul 13, 2026
07:38
Measuring In Vitro ATPase Activity for Enzymatic Characterization
Published on: August 23, 2016
Distinct static and dynamic interactions control ATPase-peptidase communication in a AAA+ protease
Andreas Martin1, Tania A Baker, Robert T Sauer
1Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Molecular Cell
|July 7, 2007
Summary
The ClpXP machine uses static and dynamic interactions between ClpX and ClpP proteins to control protein degradation. These distinct binding modes ensure stable complex formation and regulate essential functions like ATP hydrolysis and substrate unfolding.
Area of Science:
- Biochemistry
- Molecular Biology
- Proteostasis
Background:
- The ClpXP proteolytic machine is crucial for cellular protein quality control.
- ClpX, an ATPase, unfolds and translocates substrates into the ClpP protease for degradation.
Purpose of the Study:
- To elucidate the distinct interaction modes between ClpX and ClpP.
- To understand how these interactions regulate ClpXP machine function.
Main Methods:
- Biochemical assays to study ClpX-ClpP complex formation.
- Analysis of nucleotide-dependent interactions and their impact on activity.
Main Results:
- A bipartite interaction system between ClpX and ClpP was identified.
- High-affinity peripheral interactions stabilize the complex and enhance degradation.
- Dynamic axial interactions, sensitive to nucleotide state, regulate ATP hydrolysis and unfolding.
Conclusions:
- Discrete static and dynamic interactions are essential for ClpXP function.
- Peripheral interactions provide stability, while axial interactions mediate regulation.
- This dual interaction mechanism ensures efficient protein degradation and cellular proteostasis.
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