Department of Chemistry, Whitman College, Walla Walla, Washington 99362 USA
We present a new method for the determination of bilayer structure based
on a combination of computational studies and laboratory experiments.
From molecular dynamics simulations, the volumes of submolecular
fragments of saturated and unsaturated phosphatidylcholines in
the liquid crystalline state have been extracted with a precision
not available experimentally. Constancy of component volumes,
both among different lipids and as a function of membrane position
for a given lipid, have been examined. The component volumes were
then incorporated into the liquid crystallographic method described
by Wiener and White (1992. Biophys. J. 61:434-447, and references
therein) for determining the structure of a fluid-phase dioleoylphosphatidylcholine
bilayer from x-ray and neutron diffraction experiments.