The diversity of the liquid ordered (Lo) phase of phosphatidylcholine/cholesterol membranes: a variable temperature multinuclear solid-state NMR and x-ray diffraction study.

ABSTRACT: To investigate the properties of a pure liquid ordered (Lo) phase in a model membrane system, a series of saturated phosphatidylcholines combined with cholesterol were examined by variable temperature multinuclear (1H, 2H, 13C, 31P) solid-state NMR spectroscopy and x-ray scattering. Compositions with cholesterol concentrations>or=40 mol %, well within the Lo phase region, are shown to exhibit changes in properties as a function of temperature and cholesterol content. The 2H-NMR data of both cholesterol and phospholipids were used to more accurately map the Lo phase boundary. It has been established that the gel-Lo phase coexistence extends to 60 mol % cholesterol and a modified phase diagram is presented. Combined 1H-, 2H-, 13C-NMR, and x-ray scattering data indicate that there are large c

SUBMITTER: Clarke JA 

PROVIDER: S-EPMC1403185 | biostudies-literature | 2006 Apr

REPOSITORIES: biostudies-literature