The influences of lanosterol on lipid bilayers have been compared to those of cholesterol by combining deuterium (2H) NMR spin relaxation studies with segmental order parameter measurements. For bilayers of 1,2-diperdeuteriomyristoyl-sn-glycero-3-phosphocholine (DMPC-d54), the results are consistent with a square-law dependence of the 2H Zeeman relaxation rates (R1Z) on the corresponding order ...

Aqueous dispersions of the anionic phospholipid dimyristoyl phosphatidylglycerol (DMPG), around 100 mM ionic strength, are known to exhibit a thermal behavior similar to that of the largely studied lipid dimyristoyl phosphatidylcholine (DMPC), which undergoes a gel to liquid crystalline phase transition at 23 degrees C, well characterized by differential scanning calorimetry (DSC), and other me...

Small angle neutron scattering (SANS) with contrast variation was used to obtain the low resolution structure of nascent HDL (nHDL) reconstituted with dimyristoyl phosphatidyl choline (DMPC) in the absence and presence of cholesterol, [apoA1:DMPC (1:80, mol:mol) and apoA1:DMPC:Cholesterol (1:86:9, mol:mol:mol)]. The overall shape of both particles is discoidal with the low resolution structure ...

In the present work, we describe the synthesis of a single-chain, phenylene-modified bolalipid with two phosphocholine headgroups, PC-C18pPhC18-PC, using a Sonogashira cross-coupling reaction as a key step. The aggregation behaviour was studied as a function of temperature using transmission electron microscopy (TEM), differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR) sp...

The structure of softly supported polymer-cushioned lipid bilayers, prepared in two different ways at the quartz-solution interface, were determined using neutron reflectometry. The polymer cushion consisted of a thin layer of branched, cationic polyethyleneimine (PEI), and the bilayers were formed by adsorption of small unilamellar dimyristoylphosphatidylcholine (DMPC) vesicles. When vesicles ...

An atomic-scale understanding of cationic lipid membranes is required for development of gene delivery agents based on cationic liposomes. To address this problem, we recently performed molecular dynamics (MD) simulations of mixed lipid membranes comprised of cationic dimyristoyltrimethylammonium propane (DMTAP) and zwitterionic dimyristoylphosphatidylcholine (DMPC) (Biophys. J. 2004, 86, 3461-...

Previous investigations have elaborated on the necessity for dimyristoylphosphatidylcholine (DMPC) molecules to conform in a ripple phase at the temperature intermediate between the transition and pretransition in order to protect the hydrophilic-hydrophobic polarity of the bilayer. Present observations, in addition to the asymmetric P beta phase of 11.1 +/- 1.3 nm wave-length, demonstrate orth...

We have performed molecular dynamics simulations of atomistic models of C60 molecules and DMPC bilayer membranes to study the static and dynamic effects of carbon nanoparticles on biological membranes. All four C60-membrane systems were investigated representing dilute and concentrated solutions of C60 residing either inside or outside the membrane. The concentrated C60 molecules in water phase...