The free-energy profile for N2O in a hydrated 1,2-dimyristoylphosphatidylcholine (DMPC) phospholipid bilayer is calculated. The N2O molecule is preferentially concentrated in the tail region of the DMPC lipid and there is no free-energy barrier for the diffusion of N2O from an aqueous environment into the lipid. Although the dipole moment of N2O is rather small, our calculation indicates that t...

To investigate the dynamics of exchange/transfer of lipids between membranes, we have studied the interaction of donor-deuterated DMPC vesicles with DMPC hybrid bilayers on Au nanoshells using SERS. Experimental data confirm partial lipid exchange/transfer in the outer leaflet of the hybrid bilayer. The kinetics of the exchange/transfer process follows a first order process with a rate constant...

Sporidesmin, a mycotoxin from Pithomyces chartarum is a hydrophobic molecule. It can therefore be easily incorporated in the cell membrane, where it is likely to cause changes in the bilayer organization and the properties of membrane proteins. In order to understand the redox behaviour of sporidesmin in a hydrophobic environment, we have investigated the effects of oxidized and reduced sporide...

Low-angle and wide-angle X-ray diffraction was used to examine the phase behavior, as a function of temperature, of fully hydrated multilamellar vesicles of dimyristoylphosphatidylcholine (DMPC) labeled with a difluoromethylene group in the sn-2 acyl chain at position 4,8, or 12. At temperatures near 5 OC, DMPC and 2-[ 12,12-FzIDMPC are both in the Lb (gel) phase with a D-spacing of 59.5 i 0.5 ...

The membrane interactions of the antimicrobial peptide aurein 1.2 were studied using a range of biophysical techniques to determine the location and the mechanism of action in DMPC (dimyristoylphosphatidylcholine) and DMPC/DMPG (dimyristoylphosphatidylglycerol) model membranes that mimic characteristics of eukaryotic and prokaryotic membranes, respectively. Neutron reflectometry and solid-state...

Cationic lipid membranes are known to form compact complexes with DNA and to be effective as gene delivery agents both in vitro and in vivo. Here we employ molecular dynamics simulations for a detailed atomistic study of lipid bilayers consisting of a mixture of cationic dimyristoyltrimethylammonium propane (DMTAP) and zwitterionic dimyristoylphosphatidylcholine (DMPC). Our main objective is to...

Transient absorption spectroscopy was used to investigate the dynamics of the photochromic indolinobenzospiropyran reaction in toluene solution and in phosphatidylcholine bilayers (1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), and 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC)). After excitation with UV light, colorless (R/S)-2-(3',3'-d...

We have shown that bicelles prepared from dilauryl phosphatidylcholine (DLPC) and dipalmitoyl phosphatidylcholine (DPPC) align in a magnetic field under conditions similar to the more common dimyristoyl phosphatidylcholine (DMPC) bicelles. In addition, a model transmembrane peptide, P16, with a hydrophobic stretch of 24 A, and specific alanine-d(3) labels, was incorporated into all of the diffe...

Nanodiscs are phospholipid-protein complexes which are relevant to nascent high-density lipoprotein and are applicable as a drug carrier and a tool to immobilize membrane proteins. We evaluated the structure and dynamics of the nanoparticles consisting of dimyristoylphosphatidylcholine (DMPC) and apolipoprotein A-I (apoA-I) with small-angle neutron scattering (SANS) and fluorescence methods and...

This study deals with the structural perturbations that the aminoglycoside antibiotic gentamicin (GENT) can produce to phospholipid bilayers. Two multi-bilayer systems, one built-up of dimyristoylphosphatidylcholine (DMPC) and the other of dimyristoylphosphatidylethanolamine (DMPE) were allowed to interact with GENT. The experiments were performed in both a hydrophobic and a hydrophilic medium ...