Specific Unbinding Forces Between Mutated Human P-Selectin Glycoprotein Ligand-1 and Viral Protein-1 Measured Using Force Spectroscopy.

Protein tyrosine sulfation (PTS) is a key modulator of extracellular protein-protein interaction (PPI), which regulates principal biological processes. For example, the capsid protein VP1 of enterovirus 71 (EV71) specifically interacts with sulfated P-selectin glycoprotein ligand-1 (PSGL-1) to facilitate virus invasion. Currently available methods cannot be used to directly observe PTS-induced PPI.