Molecular dynamics simulations of bilayers containing mixtures of sphingomyelin with cholesterol and phosphatidylcholine with cholesterol.
We performed six molecular dynamics simulations: three on hydrated bilayers containing pure phospholipids and three on hydrated bilayers containing mixtures of these phospholipids with cholesterol. The phospholipids in our simulations were SSM (sphingomyelin containing a saturated 18:0 acyl chain), OSM (sphingomyelin with an unsaturated 18:1 acyl chain), and POPC (palmitoyloleoylphosphatidylcholine containing one saturated and one unsaturated chain). Data from our simulations were used to study systematically the effect of cholesterol on phospholipids that differed in their headgroup and tail composition. In addition to the structural analysis, we performed an energetic analysis and observed that energies of interaction between cholesterol and neighboring SM molecules are similar to the energies of interaction between cholesterol and POPC. We also observed that the interaction energy between cholesterol and neighboring lipids cannot be used for the determination of which lipids are involved in the creation of a complex.
Zhang
Zhancheng
Z
Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, USA.
Bhide
Shreyas Y
SY
Berkowitz
Max L
ML
D002784:Cholesterol / Q000737:chemistry*; D003198:Computer Simulation; D008051:Lipid Bilayers / Q000737:chemistry*; D008956:Models, Chemical; D010713:Phosphatidylcholines / Q000737:chemistry*; D013109:Sphingomyelins / Q000737:chemistry*; D013816:Thermodynamics
D008051:Lipid Bilayers; D010713:Phosphatidylcholines; D013109:Sphingomyelins; D002784:Cholesterol