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Reduced sterol-phospholipid recognition in curved fluid bilayers.

ABSTRACT: Nearest-neighbor recognition experiments have been carried out in fluid liposomal membranes made from 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and cholesterol using exchangeable dimers derived from 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine and cholesterol. In cholesterol-rich bilayers, the association between these two exchangeable lipids was reduced as the curvature of the membrane increases; that is, when the diameter of the liposomes was below ca. 200 nm. In sharp contrast, the mixing of these exchangeable lipids was close to random in the cholesterol-poor membranes, regardless of their curvature. The biological implications of these findings are briefly discussed.

SUBMITTER: Mitomo H

PROVIDER: S-EPMC2674620 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature

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Reduced sterol-phospholipid recognition in curved fluid bilayers.

Mitomo Hideyuki H Chen Wen-Hua WH Regen Steven L SL

Langmuir : the ACS journal of surfaces and colloids 20090401 8

Nearest-neighbor recognition experiments have been carried out in fluid liposomal membranes made from 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and cholesterol using exchangeable dimers derived from 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine and cholesterol. In cholesterol-rich bilayers, the association between these two exchangeable lipids was reduced as the curvature of the membrane increases; that is, when the diameter of the liposomes was below ca. 200 nm. In sharp contrast, t ...[more]

PMID: 19301879

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