Effect of the aminoacid composition of model α-helical peptides on the physical properties of lipid bilayers and peptide conformation: a molecular dynamics simulation

0424490 - ÚVGZ 2014 RIV CZ eng J - Journal Article
Melicherčík, Milan - Holúbeková, A. - Hianik, T. - Urban, J.
Effect of the aminoacid composition of model α-helical peptides on the physical properties of lipid bilayers and peptide conformation: a molecular dynamics simulation.
Journal of Molecular Modeling. Roč. 19, č. 11 (2013), s. 4723-4730. ISSN 1610-2940. E-ISSN 0948-5023
Institutional support: RVO:67179843
Keywords : Bilayer lipid membranes * Helical peptides * Molecular dynamics simulations * Phase transitions
Subject RIV: BO - Biophysics
Impact factor: 1.867, year: 2013

The interaction of a model Lys flanked α-helical peptides K2-X24-K2, (X = A,I,L,L+A,V) with lipid bilayers composed of dimyristoylphosphatidylcholine (DMPC) and dipalmitoylphosphatidylcholine (DPPC) both, in a gel and in a liquid-crystalline state, has been studied by molecular dynamics simulations. It has been shown that these peptides cause disordering of the lipid bilayer in the gel state but only small changes have been monitored in a liquid-crystalline state. The peptides affect ordering of the surrounding lipids depending on the helix stability which is determined by amino acid side chains – their volume, shape, etc. We have shown that the helix does not keep the linear shape in all simulations but often bends or breaks. During some simulations with a very small difference between hydrophobic length of peptide and membrane thickness the peptide exhibits negligible tilt. At the same time changes in peptide conformations during simulations resulted in appearance of superhelix.
Permanent Link: http://hdl.handle.net/11104/0230581