Cross-affinity of Peptide Ligands Selected from Phage Display Library Against Pancreatic Phospholipase A2 and Ammodytoxin C

Two phage-displayed random peptide libraries were screened for ligands with potential inhibitory activity against pancreatic phospolipase A2 or ammodytoxin C (neurotoxin found in the venom glands of Vipera ammodytes ammodytes). The interaction of selected peptides with pancreatic phospholipase A2 and ammodytoxin C was confirmed with surface plasmon resonance and phage ELISA assays. Interestingly, peptides showed equal affinity to both proteins, regardless which of the two proteins was used as a target in the selection procedure. Despite pronounced affinity, none of the synthetic peptides inhibited enzyme targets in vitro at the concentrations below 167 μM.