Shape modification of phospholipid vesicles induced by high pressure: influence of bilayer compressibility.
AUTOR(ES)
Beney, L
RESUMO
Giant vesicles composed of pure egg yolk phosphatidylcholine (EYPC) or containing cholesterol (28 mol%) have been studied during a high hydrostatic pressure treatment to 285 MPa by microscopic observation. During pressure loading the vesicles remain spherical. A shape transition consisting of budding only occurs on the cholesterol-free vesicles during pressure release. The decrease in the volume delimited by the pure EYPC bilayer between 0.1 and 285 MPa was found to be 16% of its initial volume, whereas the bulk compression of water in this pressure range is only 10%. So the compression at 285 MPa induced a water exit from the pure EYPC vesicle. The shape transition of the EYPC vesicle during pressure release is attributed to an increase in its area-to-volume ratio caused by the loss of its water content during compression. Because bulk compression of the cholesterol-containing vesicle is close to that of water, no water transfer would be induced across the bilayer and the vesicle remains spherical during the pressure release.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1184508Documentos Relacionados
- Formation and properties of 1000-A-diameter, single-bilayer phospholipid vesicles.
- Hydrostatic pressure in small phospholipid vesicles
- Effect of surface modification on aggregation of phospholipid vesicles.
- Dissociation of molecular aggregates under high hydrostatic pressure: the influence of water structure on Benzene cluster solubility
- Protonic conductance across phospholipid bilayer membranes induced by uncoupling agents for oxidative phosphorylation.