A Review of the Mechanism of Action of Amphibian Antimicrobial Peptides Focusing on Peptide-Membrane Interaction and Membrane Curvature

Research interests on amphibian antimicrobial peptides (AMPs) are currently increasing because of their capability to combat microorganisms from both terrestrial and aquatic environments, which are the warehouses of human pathogens. The most remarkable feature of AMPs are their mechanism of action, primarily targeted to anionic membranes. Researchers have postulated many models to describe peptide-membrane interaction, which leads to membrane permeation/intracellular targeting. Despite these models information regarding the relationship between membrane curvature and peptide-membrane interaction is scarce. This relationship could be clearly depicted using the two-state model and interfacial activity model. In the review, we discuss in detail the two state and interfacial activity models and explain the influence of membrane curvature on peptide binding and the membrane interaction of curvature-sensitive peptides. In addition, the models proposed to explain the mechanism of action of membrane lytic and non-lytic AMPs are also reviewed.