Lateral diffusion coefficients of separate lipid species in a ternary raft-forming bilayer: A Pfg-NMR multinuclear study

Title

Lateral diffusion coefficients of separate lipid species in a ternary raft-forming bilayer: A Pfg-NMR multinuclear study

Creator

Oradd G; Westerman P W; Lindblom G

Publisher

Biophysical Journal

Date

2005
2005-07

Description

By isotopical labeling lipid lateral diffusion coefficients for each of the membrane constituents, including cholesterol, have been measured by H-1, H-2, and F-19 pulsed field gradient NMR spectroscopy in macroscopically oriented lipid bilayers. This provides a means of obtaining detailed dynamic and compositional information in raft-forming lipid bilayers without introducing foreign molecules into the systems. The raft systems studied contained dioleoylphosphatidylcholine/dipalmitoylphosphatidylcholine (DPPC)/cholesterol at the molar ratios of 42.5: 42.5: 15 and 35: 35: 30 in excess water. At temperatures below 30 degrees C the raft system forms large (>1 mu m) domains of a liquid ordered (l(o)) phase, in which the lipid lateral diffusion was; 5 times slower than for the lipids in the surrounding liquid disordered (l(d)) phase. Within each domain all lipid species showed the same diffusion coefficient, despite the very different structures of cholesterol and phospholipids. DPPC partitions exclusively into the l(o) domains, whereas cholesterol and dioleoylphosphatidylcholine were distributed in both l(o) and l(d) phases. The cholesterol concentration was found to be 10-20 mol% in the l(d) domain and 30-40 mol% in the l(o) domain. Comparison of these results with data from sphingomyelin-containing systems suggests that DPPC interacts more weakly with cholesterol than does sphingomyelin.

Subject

atomic-force microscopy; Biophysics; cell-membranes; fluorescence correlation spectroscopy; insulin-receptor; least-squares analysis; model membranes; phase-equilibria; plasma-membrane; signal-transduction; spectral data sets

Format

Journal Article

Search for Full-text

Users with a NEOMED Library login can search for full-text journal articles at the following url: https://libraryguides.neomed.edu/home

Rights

Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).

Pages

315-320

Issue

1

Volume

89

Citation

Oradd G; Westerman P W; Lindblom G, “Lateral diffusion coefficients of separate lipid species in a ternary raft-forming bilayer: A Pfg-NMR multinuclear study,” NEOMED Bibliography Database, accessed May 12, 2021, https://neomed.omeka.net/items/show/6689.

Social Bookmarking