Identification and Characterization of Strychnine-Binding Peptides Using Phage-Display Screening.

Background: In drug development, phage display is a high-throughput method for identifying the specific cellular targets of drugs. However, insoluble small chemicals remain intractable to this technique because of the difficulty of presenting molecules to phages without occupying or destroying the limited functional groups.

Objectives: In the present study, we selected Strychnine (Stry) as a model compounda and sought to develope an alternative in vitro biopanning strategy against insoluble suspension.

Method: A phage library displaying random sequences of fifteen peptides was employed to screen for interactions between Stry and its cellular selective binding peptides, which are of great value to have a complete understanding of the mechanism of Stry for its antitumor activity.

Results: After four rounds of biopanning, a selection of 100 binding clones was randomly picked and subjected to modified proliferation and diffusion assays to evaluate the binding affinity of the clones. Finally, eleven clones were identified as positive binders. The corresponding peptides were synthesized and detected for their binding activities using surface plasmon resonance imaging (SPRi).

Conclusion: Our study provides a feasible scheme for confirming the interaction of chemical compounds and cellular binding peptides.