Catch Bond-Mediated Adhesion Drives <i>Staphylococcus aureus</i> Host Cell Invasion.

Abstract

Various viruses and pathogenic bacteria interact with annexin A2 to invade mammalian cells. Here, we show that <i>Staphylococcus aureus</i> engages in extremely strong catch bonds for host cell invasion. By means of single-molecule atomic force microscopy, we find that bacterial surface-located clumping factors bind annexin A2 with extraordinary strength, indicating that these bonds are extremely resilient to mechanical tension. By determining the lifetimes of the complexes under increasing mechanical stress, we demonstrate that the adhesins form catch bonds with their ligand that are capable to sustain forces of 1500-1700 pN. The force-dependent adhesion mechanism identified here provides a molecular framework to explain how <i>S. aureus</i> pathogens tightly attach to host cells during invasion and shows promise for the design of new therapeutics against intracellular <i>S. aureus</i>.