Lateral pressure profiles in cholesterol-DPPC bilayers.
By means of atomistic molecular dynamics simulations, we study cholesterol-DPPC (dipalmitoyl phosphatidylcholine) bilayers of different composition, from pure DPPC bilayers to a 1:1 mixture of DPPC and cholesterol. The lateral pressure profiles through the bilayers are computed and separated into contributions from the different components. We find that the pressure inside the bilayer changes qualitatively for cholesterol concentrations of about 20% or higher. The pressure profile in the inside of the bilayer then turns from a rather flat shape into an alternating sequence of regions with large positive and negative lateral pressure. The changes in the lateral pressure profile are so characteristic that specific interaction between cholesterol and molecules such as membrane proteins mediated solely via the lateral pressure profile might become possible.
Patra
Michael
M
Biophysics and Statistical Mechanics Group, Laboratory of Computational Engineering, Helsinki University of Technology, P. O. Box 9203, 02015 HUT, Finland. patra@lorentz.leidenuniv.nl
D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry*; D002784:Cholesterol / Q000737:chemistry*; D007473:Ion Channels / Q000378:metabolism; D008051:Lipid Bilayers / Q000737:chemistry*; D008968:Molecular Conformation; D013314:Stress, Mechanical; D013499:Surface Properties; D013816:Thermodynamics
D007473:Ion Channels; D008051:Lipid Bilayers; D015060:1,2-Dipalmitoylphosphatidylcholine; D002784:Cholesterol