Biophysical Journal 59: 31-38 (1991)
© 1991 the Biophysical Society

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Auger, M Articles by Jarrell, H C Search for Related Content PubMed PubMed Citation Articles by Auger, M Articles by Jarrell, H C

Slow motions in lipid bilayers. Direct detection by two-dimensional solid-state deuterium nuclear magnetic resonance.

Division of Biological Sciences, National Research Council of Canada, Ottawa, Ontario.

ABSTRACT

Two-dimensional solid-state 2H NMR spectroscopy of specifically deuteriated lipids is used to detect and to characterize the rate and mode of slow motions in two lipid bilayer systems. Lateral diffusion of lipid molecules over the curved surface of dipalmitoylphosphatidylcholine liposomes can be detected by two-dimensional exchange 2H NMR and it is shown that molecular orientational exchange is complete on the timescale of 100 ms. In contrast, it is shown that for the glycolipid 1,2-di-O-tetradecyl-3-O-Beta-D-glucopyranosyl)-sn-glycerol (beta-DTGL), there is no evidence of a corresponding orientational exchange in the liquid-crystalline phase suggesting that this lipid forms relatively flat bilayers. In the gel phase of hydrated multibilayers of beta-DTGL, a slow (10(3) s(-1)) whole molecule axial motion is demonstrated at 40 degrees C. Comparison of the experimental and simulated 2D-NMR ridge patterns suggests that large angle jumps about the long molecular axis, rather than small step Brownian diffusion, can best account for the 2D-exchange spectra of beta-DTGL in the gel phase. The significance of this technique for the study of dynamics in other biological systems is discussed.