Stable Peptides Instead of Stapled Peptides: Highly Potent αvβ6-Selective Integrin Ligands.

The αvβ6 integrin binds the RGD-containing peptide of the foot and mouth disease virus with high selectivity. In this study, the long binding helix of this ligand was downsized to an enzymatically stable cyclic peptide endowed with sub-nanomolar binding affinity toward the αvβ6 receptor and remarkable selectivity against other integrins. Computational studies were performed to disclose the molecular bases underlying the high binding affinity and receptor subtype selectivity of this peptide. Finally, the utility of the ligand for use in biomedical studies was also demonstrated here.