Indolicidin binding induces thinning of a lipid bilayer.

We use all-atom molecular dynamics simulations on a massive scale to compute the standard binding free energy of the 13-residue antimicrobial peptide indolicidin to a lipid bilayer. The analysis of statistical convergence reveals systematic sampling errors that correlate with reorganization of the bilayer on the microsecond timescale and persist throughout a total of 1.4 ms of sampling.

Cationic peptide-induced remodelling of model membranes: direct visualization by in situ atomic force microscopy.

Our understanding of how antimicrobial and cell-penetrating peptides exert their action at cell membranes would benefit greatly from direct visualization of their modes of action and possible targets within the cell membrane. We previously described how the cationic antimicrobial peptide, indolicidin, interacted with mixed zwitterionic planar lipid bilayers as a function of both peptide concentration and lipid composition [Shaw, J.E.

Molecular dynamics simulations of indolicidin association with model lipid bilayers.

Identifying the mechanisms responsible for the interaction of peptides with cell membranes is critical to the design of new antimicrobial peptides and membrane transporters. We report here the results of a computational simulation of the interaction of the 13-residue peptide indolicidin with single-phase lipid bilayers of dioleoylphosphatidylcholine, distearoylphosphatidylcholine, dioleoylphosphatidylglycerol, and distearoylphosphatidylglycerol. Ensemble analysis of the membrane-bound peptide revealed that, in contrast to the extended, linear backbone structure reported for indolicidin in sodium dodecyl sulphate detergent micelles, the peptide adopts a boat-shaped conformation in both phosphatidylglycerol and phosphatidylcholine lipid bilayers, similar to that reported for dodecylphosphocholine micelles.