Catch Bond-Mediated Adhesion Drives Staphylococcus aureus Host Cell Invasion

Area of Science:

• Microbiology
• Molecular Biology
• Biophysics

Background:

• Pathogenic bacteria and viruses utilize host cell protein annexin A2 for cellular invasion.
• Staphylococcus aureus is a significant pathogen known to interact with host cells.

Purpose of the Study:

• To investigate the molecular mechanism of Staphylococcus aureus host cell invasion.
• To characterize the adhesive interactions between bacterial surface proteins and annexin A2.

Main Methods:

• Single-molecule atomic force microscopy was employed to analyze molecular interactions.
• The lifetimes of protein complexes were measured under varying mechanical stress.

Main Results:

• Staphylococcus aureus clumping factors form exceptionally strong catch bonds with annexin A2.
• These bonds exhibit remarkable resilience, sustaining forces of 1500-1700 pN.
• A force-dependent adhesion mechanism was identified.

Conclusions:

• The identified catch bond mechanism explains the tight attachment of S. aureus to host cells during invasion.
• This discovery provides a molecular framework for developing novel therapeutics against intracellular S. aureus.