title: High hydrostatic pressure effects investigated by neutron scattering on lipid multilamellar vesicles.
abstract: The effects of high hydrostatic pressure on the structure and dynamics of model membrane systems were investigated using neutron scattering. Diffraction experiments show shifts of the pre- and main-phase transitions of multilamellar vesicles of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) to higher temperatures with increased pressure which are close to results observed previously by other techniques, namely (10.4 ± 1.0) K kbar(-1) and (20.0 ± 0.5) K kbar(-1) for the two transitions. Backscattering spectroscopy reveals that the mean square displacements in the liquid phase are about 10% smaller at 300 bar and about 20% smaller at 600 bar compared to atmospheric pressure, whereas in the gel phase below the main phase transition the mean square displacements show a smaller difference in the dynamics of the three pressure values within the studied pressure range.
authors.affiliation: Angewandte Physikalische Chemie, Universität Heidelberg, Im Neuenheimer Feld 253, 69120 Heidelberg, Germany.
authors.forename: Marcus
authors.initials: M
authors.lastname: Trapp
authors.forename: Jérémie
authors.initials: J
authors.lastname: Marion
authors.forename: Moeava
authors.initials: M
authors.lastname: Tehei
authors.forename: Bruno
authors.initials: B
authors.lastname: Demé
authors.forename: Thomas
authors.initials: T
authors.lastname: Gutberlet
authors.forename: Judith
authors.initials: J
authors.lastname: Peters
mesh_terms: D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry*; D006874:Hydrostatic Pressure; D008081:Liposomes / Q000737:chemistry*; D033363:Neutron Diffraction; D044367:Phase Transition; D013696:Temperature
chemical_list: D008081:Liposomes; D004134:Dimyristoylphosphatidylcholine