Search results for "Spontaneous curvature"

showing 2 items of 2 documents

Shape transitions of giant liposomes induced by an anisotropic spontaneous curvature

2000

International audience; We explore how a magnetic field breaks the symmetry of an initially spherical giant liposome filled with a magnetic colloid. The condition of rotational symmetry along the field axis leads either to a prolate or to an oblate ellipsoid. We demonstrate that an electrostatic interaction between the nanoparticles and the membrane triggers the shape transition. PACS numbers: 75.

Field (physics)Static ElectricityRotational symmetryFOS: Physical sciencesNanoparticle02 engineering and technologyCondensed Matter - Soft Condensed Matter[CHIM.INOR]Chemical Sciences/Inorganic chemistryCurvatureFerric Compounds01 natural sciencesMagneticsColloid0103 physical sciencesColloids010306 general physicsAnisotropyDebye lengthPhysicsCondensed matter physicsOsmolar Concentration[CHIM.MATE]Chemical Sciences/Material chemistryModels Theoretical021001 nanoscience & nanotechnologyGiant liposomesSymmetry (physics)Magnetic field[CHIM.POLY]Chemical Sciences/PolymersClassical mechanicsLiposomesMagnetic nanoparticlesPhosphatidylcholinesSoft Condensed Matter (cond-mat.soft)AnisotropySpontaneous curvature0210 nano-technology[PHYS.COND.CM-SCM]Physics [physics]/Condensed Matter [cond-mat]/Soft Condensed Matter [cond-mat.soft]Physical Review E
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(19)F NMR screening of unrelated antimicrobial peptides shows that membrane interactions are largely governed by lipids.

2014

AbstractMany amphiphilic antimicrobial peptides permeabilize bacterial membranes via successive steps of binding, re-alignment and/or oligomerization. Here, we have systematically compared the lipid interactions of two structurally unrelated peptides: the cyclic β-pleated gramicidin S (GS), and the α-helical PGLa. 19F NMR was used to screen their molecular alignment in various model membranes over a wide range of temperatures. Both peptides were found to respond to the phase state and composition of these different samples in a similar way. In phosphatidylcholines, both peptides first bind to the bilayer surface. Above a certain threshold concentration they can re-align and immerse more dee…

Membrane lipidsAntimicrobial peptidesAmphiphilic antimicrobial peptidesLipid BilayersBiophysicsBiochemistryProtein Structure Secondarychemistry.chemical_compoundMembrane LipidsHumansAmino Acid SequenceProtein PrecursorsLipid bilayerNuclear Magnetic Resonance BiomolecularBacteriaBilayerPeripheral membrane proteinLipid compositionCell MembraneGramicidinBiological membraneRe-alignment in membraneCell BiologyMembraneBiochemistrychemistryGramicidinBiophysicsBacterial membranesSpontaneous curvatureSolid state 19F NMR structure analysis
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