Biophysical Journal 66: 1457-1468 (1994)
© 1994 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 HighWire Citing Articles via Google Scholar Google Scholar Articles by Vanderkooi, G Search for Related Content PubMed PubMed Citation Articles by Vanderkooi, G

Computation of mixed phosphatidylcholine-cholesterol bilayer structures by energy minimization.

Department of Chemistry, Northern Illinois University, DeKalb 60115.

ABSTRACT

The energetically preferred structures of dimyristoylphosphatidylcholine (DMPC)-cholesterol bilayers were determined at a 1:1 mole ratio. Crystallographic symmetry operations were used to generate planar bilayers of cholesterol and DMPC. Energy minimization was carried out with respect to bond rotations, rigid body motions, and the two-dimensional lattice constants. The lowest energy structures had a hydrogen bond between the cholesterol hydroxyl and the carbonyl oxygen of the sn-2 acyl chain, but the largest contribution to the intermolecular energy was from the nonbonded interactions between the flat alpha surface of cholesterol and the acyl chains of DMPC. Two modes of packing in the bilayer were found; in structure A (the global minimum), unlike molecules are nearest neighbors, whereas in structure B (second lowest energy) like-like intermolecular interactions predominate. Crystallographic close packing of the molecules in the bilayer was achieved, as judged from the molecular areas and the bilayer thickness. These energy-minimized structures are consistent with the available experimental data on mixed bilayers of lecithin and cholesterol, and may be used as starting points for molecular dynamics or other calculations on bilayers.

This article has been cited by other articles:

				K. J. Tierney, D. E. Block, and M. L. Longo Elasticity and Phase Behavior of DPPC Membrane Modulated by Cholesterol, Ergosterol, and Ethanol Biophys. J., October 1, 2005; 89(4): 2481 - 2493. [Abstract] [Full Text] [PDF]

				A. Radhakrishnan and H. McConnell Condensed complexes in vesicles containing cholesterol and phospholipids PNAS, September 6, 2005; 102(36): 12662 - 12666. [Abstract] [Full Text] [PDF]

				J. A. Virtanen, K. H. Cheng, and P. Somerharju Phospholipid composition of the mammalian red cell membrane can be rationalized by a superlattice model PNAS, April 28, 1998; 95(9): 4964 - 4969. [Abstract] [Full Text] [PDF]