The Peptide Antibiotic Clavanin A Interacts Strongly and Specifically with Lipid Bilayers

In this study the interaction of the antimicrobial peptide clavanin A with phosphatidylcholine bilayers is investigated by DSC, NMR, and AFM techniques. It is shown that the peptide interacts strongly and specifically with the lipids, resulting in increased order−disorder phase transition temperatures, phase separation, altered acyl chain and headgroup packing, and a drastically changed surface morphology of the bilayer. These results are interpreted in terms of clavanin-specific interactions with lipids and are discussed in the light of the different mechanisms by which clavanin A can destroy the barrier function of biological membranes.