Molecular interaction and inhibition of SARS-CoV-2 binding to the ACE2 receptor

Study of virus entry into cells is of critical importance for a better understanding of the interactions established between the viral glycoproteins and their receptors at the cell surface and could help to develop novel antiviral strategies. The novel coronavirus (SARS-CoV-2) entry into host cells is mediated by the transmembrane spike glycoprotein (S-glycoprotein) and the angiotensin-converting enzyme 2 (ACE2) has been identified as a cellular receptor. Here, we used atomic force microscopy to investigate the molecular mechanisms by which the S- glycoprotein binds to the ACE2 receptor. We demonstrated, both on model surfaces and on living cells, that the receptor binding domain (RBD) serves as a binding interface within the S- glycoprotein with the ACE2 receptor and we extracted the kinetic and thermodynamic properties of this binding pocket. Altogether, these results give a dynamic picture of the established interaction in physiologically relevant conditions. Finally, we identified and tested several binding inhibitor peptides targeting the virus early attachment stages, offering new perspectives in the treatment of the SARS-CoV-2 infection.