Author:

Keywords:

Melittin, Lipid rafts, Cholesterol, Quartz crystal microbalance with dissipation, Science & Technology, Life Sciences & Biomedicine, Physical Sciences, Technology, Biophysics, Chemistry, Physical, Materials Science, Biomaterials, Chemistry, Materials Science, ISLET AMYLOID POLYPEPTIDE, LIPID VESICLE DEPOSITION, ANTIMICROBIAL PEPTIDE, QCM-D, PHASE-EQUILIBRIA, TERNARY MIXTURES, DELTA-LYSIN, CHOLESTEROL, BILAYER, TEMPERATURE, Biomimetics, Melitten, Membranes, Artificial, Quartz Crystal Microbalance Techniques, 0306 Physical Chemistry (incl. Structural), 0903 Biomedical Engineering, 0904 Chemical Engineering, Chemical Physics, 3406 Physical chemistry, 4003 Biomedical engineering, 4004 Chemical engineering

Abstract:

In this work we examine the role of lateral phase separation in cholesterol-containing biomimetic membranes on the disrupting action of melittin using a label-free surface-sensitive technique, quartz crystal microbalance with dissipation monitoring (QCM-D). Melittin disruption mechanisms depend strongly on the geometry of the lipid layer; however, despite the interplay between layer geometry/thickness and melittin activity, results indicate that the presence of lipid heterogeneity and lateral phase separation greatly influences the disrupting efficiency of melittin. In homogeneous non-raft forming membranes with high cholesterol content, melittin spontaneous activity is strongly delayed compared to heterogeneous raft-forming systems with the same amount of cholesterol. These results confirm the importance of lateral phase separation as a determinant factor in peptide activity. The information provided can be used for the design of more efficient antimicrobial peptides and the possibility of using a label-free approach for tailored-membranes and interactions with other types of peptides, such as amyloid peptides.