Rational modification and bioactivity testing of antimicrobial peptides belonging to three different families from skin secretions of the frog, Rana pipiens

Amphibian skin, particularly from frogs like Rana pipiens, is a rich source of diverse AMPs. This study reports the discovery and characterization of QUB-2578, a novel Brevinin-1 family AMP from R. pipiens, identified via molecular cloning.

To explore intra-species AMP diversity, we also examined Esculentin-2P and Temporin-1P, previously reported in this species. Although their co-expression remains unconfirmed, these peptides provide a model for potential functional synergy. Through rational design, we generated analogues for each peptide: QUB-2578 variants via structure–activity relationship analysis, a truncated Esculentin-2P with non-natural substitutions, and a modified Temporin-1P with enhanced membrane activity.