Abstract:
:The structure of fully hydrated gel phase dimyristoylphosphatidylcholine lipid bilayers was obtained at 10 degrees C. Oriented lipid multilayers were used to obtain high signal-to-noise intensity data. The chain tilt angle and an estimate of the methylene electron density were obtained from wide angle reflections. The chain tilt angle is measured to be 32.3 +/- 0.6 degrees near full hydration, and it does not change as the sample is mildly dehydrated from a repeat spacing of D = 59.9 A to D = 56.5 A. Low angle diffraction peaks were obtained up to the tenth order for 17 samples with variable D and prepared by three different methods with different geometries. In addition to the usual Fourier reconstructions of the electron density profiles, model electron density profiles were fit to all the low angle data simultaneously while constraining the model to include the wide-angle data and the measured lipid volume. Results are obtained for area/lipid (A = 47.2 +/- 0.5 A(2)), the compressibility modulus (K(A) = 500 +/- 100 dyn/cm), various thicknesses, such as the hydrocarbon thickness (2D(C) = 30.3 +/- 0.2 A), and the head-to-head spacing (D(HH) = 40.1 +/- 0.1 A).
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Tristram-Nagle S,Liu Y,Legleiter J,Nagle JFdoi
10.1016/S0006-3495(02)75333-2subject
Has Abstractpub_date
2002-12-01 00:00:00pages
3324-35issue
6eissn
0006-3495issn
1542-0086pii
S0006-3495(02)75333-2journal_volume
83pub_type
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