title: Surface occupancy plays a major role in cholesterol's condensing effect.
abstract: The condensing power of cholesterol and 5α-cholestane has been examined in liposomal membranes made from 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). Quantitative nearest-neighbor recognition (NNR) analysis and fluorescence measurements using phase-sensitive probe Laurdan have demonstrated that 5α-cholestane exhibits a substantially weaker condensing effect. This fact, in and of itself, provides compelling evidence that cholesterol's condensing effect is critically dependent on having its steroid nucleus at the membrane surface.
authors.affiliation: Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, USA.
authors.forename: Martin R
authors.initials: MR
authors.lastname: Krause
authors.forename: Serhan
authors.initials: S
authors.lastname: Turkyilmaz
authors.forename: Steven L
authors.initials: SL
authors.lastname: Regen
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000031:analogs & derivatives / Q000737:chemistry; D002778:Cholestanones / Q000737:chemistry; D002784:Cholesterol / Q000737:chemistry*; D008081:Liposomes / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D013329:Structure-Activity Relationship
chemical_list: D002778:Cholestanones; D008081:Liposomes; D015060:1,2-Dipalmitoylphosphatidylcholine; C081581:colfosceril palmitate; D002784:Cholesterol