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Molecular structure of the lecithin ripple phase.

ABSTRACT: Molecular dynamics simulations of lecithin lipid bilayers in water as they are cooled from the liquid crystalline phase show the spontaneous formation of rippled bilayers. The ripple consists of two domains of different length and orientation, connected by a kink. The organization of the lipids in one domain of the ripple is found to be that of a splayed gel; in the other domain the lipids are gel-like and fully interdigitated. In the concave part of the kink region between the domains the lipids are disordered. The results are consistent with the experimental information available and provide an atomic-level model that may be tested by further experiments.

SUBMITTER: de Vries AH

PROVIDER: S-EPMC556238 | biostudies-literature | 2005 Apr

REPOSITORIES: biostudies-literature

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Molecular structure of the lecithin ripple phase.

de Vries Alex H AH Yefimov Serge S Mark Alan E AE Marrink Siewert J SJ

Proceedings of the National Academy of Sciences of the United States of America 20050404 15

Molecular dynamics simulations of lecithin lipid bilayers in water as they are cooled from the liquid crystalline phase show the spontaneous formation of rippled bilayers. The ripple consists of two domains of different length and orientation, connected by a kink. The organization of the lipids in one domain of the ripple is found to be that of a splayed gel; in the other domain the lipids are gel-like and fully interdigitated. In the concave part of the kink region between the domains the lipid ...[more]

PMID: 15809443

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