LEGO-like approach to customized a bioactive peptide

Bioactive peptides (BPs) are peptides with hormonal or pharmacological properties. The source of BPs can be from natural peptides of endogenic origin, or it can be synthesized in the lab based on rational design or screening. Herein we demonstrate how a BP of interest can be modified to a highly effective research tool as well as therapeutic lead with minimal modifications that can be done in many labs or ordered in a reasonable price. As a proof of concept, we developed a linear peptide designed to bind to PTEN-induced kinase 1 (Pink1). Pink1 protein is related to mitochondrial dynamics and it was demonstrated to regulate mitochondrial homeostasis. Initially we cyclized the peptide demonstrating that the cyclic peptide has higher binding affinity and improve stability compared to the linear peptide. In addition, the cyclization will gain the peptide drug-like properties. Next we added dye to the peptide and demonstrated its colocalization with the target protein, Pink1 in H9c2 cell line. Finally, using crosslinker we identified the binding domain of the peptide and determined the interaction area, providing novel structural information about the protein. This project presents a general approach using an identified peptide and developing various research tools as well as therapeutic leads, which can be customized to other laboratories easily.