Peptide fibrils as monomer storage of the covalent HIV-1 integrase inhibitor

We have recently reported the covalent inhibition of HIV-1 integrase by an N-terminal succinimide-modified lens epithelium-derived growth factor (361–370) peptide. We also showed that this peptide is proteolytically stable. Here, we show that this inhibitor is stored as fibrils that serve as a stock for the inhibitory monomers. The fibrils increase the local concentration of the peptide at the target protein. When the monomers bind integrase, the equilibrium between the fibrils and their monomers shifts towards the formation of peptide monomers. The combination of fibril formation and subsequent proteolytic stability of the peptide may bring to new strategy for developing therapeutic agents.