Detection of phase separation in fluid phosphatidylserine/phosphatidylcholine mixtures.
Biophys J
; 67(5): 1906-11, 1994 Nov.
Article
en En
| MEDLINE
| ID: mdl-7858127
ABSTRACT
The nonideal mixing of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoserine, (160, 181)PS, and 1,2-didodecenoyl-sn-glycero-3-phosphocholine, (121, 121)PC, in fluid lamellar model membranes was studied by measuring binding of aqueous Ca2+ ions and by x-ray diffraction. A region of two-phase coexistence was found by invariance of the aqueous concentration and by the appearance of two sets of lamellar spacings. The phases were identified as fluid from the diffuse x-ray diffraction in the wide-angle region. The width of the two-phase coexistence region was greater at higher ionic strength. In 800 mM KCl, the phase boundaries were at PS mole fraction 0.5 and 0.8. In 100 mM KCl, the phase boundaries were at PS mole fraction 0.52 and 0.62. Monte Carlo simulations of the lateral distributions of these PS/PC mixtures show pronounced clustering of the lipids.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Fosfatidilgliceroles
/
Fosfatidilserinas
Tipo de estudio:
Diagnostic_studies
/
Prognostic_studies
Idioma:
En
Revista:
Biophys J
Año:
1994
Tipo del documento:
Article