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Updated: Aug 6, 2025
11:13
Covalent Immobilization of Proteins for the Single Molecule Force Spectroscopy
Published on: August 20, 2018
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High-force catch bonds between the Staphylococcus aureus surface protein SdrE and complement regulator factor H drive
Telmo O Paiva1, Joan A Geoghegan2, Yves F Dufrêne3
1Louvain Institute of Biomolecular Science and Technology, UCLouvain, Croix du Sud, 4-5, L7.07.07, B-1348, Louvain-la-Neuve, Belgium.
Communications Biology
|March 22, 2023
Summary
The Staphylococcus aureus protein SdrE uses a unique high-force catch bond to bind factor H, aiding immune evasion. This mechanism, driven by stress-induced conformational changes, offers a potential therapeutic target against resistant bacterial strains.
Area of Science:
- Microbiology
- Immunology
- Biophysics
Background:
- Staphylococcus aureus is an invasive pathogen that evades the human immune system.
- It achieves this by recruiting the complement regulatory protein, factor H (fH), to its surface.
Purpose of the Study:
- To identify and characterize the binding mechanism between S. aureus surface protein SdrE and factor H under mechanical stress.
- To explore the potential of this interaction as a therapeutic target.
Main Methods:
- Investigated the SdrE-fH interaction using single-molecule force spectroscopy.
- Analyzed bond dynamics and lifetime under varying mechanical forces.
- Examined conformational changes in SdrE using a "dock, lock and latch" model.
Main Results:
- Identified an extremely high-force catch bond between SdrE and fH, with bond lifetime increasing up to 1,400 pN.
- Observed a transition to slip bond behavior at forces above 1,400 pN.
- Dissected the catch-bond mechanism, involving stress-induced conformational changes in SdrE leading to stable hydrogen bonds with fH.
Conclusions:
- The SdrE-fH interaction utilizes a novel catch-bond mechanism crucial for S. aureus immune evasion.
- Understanding this force-dependent binding is key to developing new strategies against multidrug-resistant S. aureus.
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