Reduced sterol-phospholipid recognition in curved fluid bilayers.
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.
Mitomo
Hideyuki
H
Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, USA.
Chen
Wen-Hua
WH
Regen
Steven L
SL
D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry; D002627:Chemistry, Physical / Q000379:methods; D002784:Cholesterol / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D006358:Hot Temperature; D008051:Lipid Bilayers; D008055:Lipids / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008560:Membrane Fluidity; D008956:Models, Chemical; D010743:Phospholipids / Q000737:chemistry*; D013261:Sterols / Q000737:chemistry*; D013499:Surface Properties; D013696:Temperature
D008051:Lipid Bilayers; D008055:Lipids; D008081:Liposomes; D010743:Phospholipids; D013261:Sterols; D015060:1,2-Dipalmitoylphosphatidylcholine; D002784:Cholesterol