6533b836fe1ef96bd12a0bb0

RESEARCH PRODUCT

Phase coexistence in a triolein-phosphatidylcholine system. Implications for lysosomal membrane properties.

John Hjort IpsenMatti VuentoLars DuelundKirsi I. Pakkanen

subject

Membrane FluidityLipid BilayersPhospholipidCalorimetryBiochemistryPhase TransitionGlycerideschemistry.chemical_compoundPhosphatidylcholineMembrane fluidityTransition TemperatureTrioleinMolecular BiologyPOPCChromatographyCalorimetry Differential ScanningOrganic ChemistryElectron Spin Resonance SpectroscopyWaterCell BiologyPenetration (firestop)MembranechemistryBiophysicsPhosphatidylcholineslipids (amino acids peptides and proteins)LysosomesTriolein

description

The effects of tri- and monoglycerides on phospholipid (POPC) membranes were studied using spectroscopical methods. Triolein was found to form two types of POPC-rich membranes, both with POPC or as a three-component system with monopalmitin. These two membrane types were determined as co-existing phases based on their spontaneous and stable separation and named heavy and light phase according to their sedimentation behaviour. Marked differences were seen in the physical properties of these phases, even though only minor compositional variation was detected. The light, less polar phase was found to be less ordered and more fluid and seemed to allow significantly lower amount of water penetration into the membrane-water interface than pure POPC membrane. The heavy phase, apart from their slightly altered water penetration, resembled more a pure POPC membrane. As triglycerides are present in lysosomal membranes, the present results can be seen as an implication for polarity-based water permeability barrier possibly contributing to the integrity of lysosomes.

10.1016/j.chemphyslip.2009.11.007https://pubmed.ncbi.nlm.nih.gov/19962372