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Viewing membrane-bound molecular umbrellas by parallax analyses.

ABSTRACT: Fluorescence quenching measurements have been made for a series of di-walled and tetra-walled molecular umbrellas having moderate (i.e., hydroxyl-) and strong (i.e., sulfate-) facial hydrophilicity, using Cascade Blue as the fluorophore. Through the use of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphotempocholine, 1-palmitoyl-2-stearoyl-(5-DOXYL)-sn-glycero-3-phosphocholine, and 1-palmitoyl-2-stearoyl-(12-DOXYL)-sn-glycero-3-phosphocholine as fluorescence quenchers, evidence has been obtained for a membrane-bound state in which the umbrella molecules lie on the surface of the lipid bilayer. In the case of the sulfated molecular umbrellas, evidence has also been obtained for a subpopulation in which the fluorophore lies deeper within the membrane. Probable structures for the shallow-lying and deep-lying molecular umbrellas are discussed.

SUBMITTER: Kondo M

PROVIDER: S-EPMC2822653 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

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Viewing membrane-bound molecular umbrellas by parallax analyses.

Kondo Masaharu M Mehiri Mohamed M Regen Steven L SL

Journal of the American Chemical Society 20080911 41

Fluorescence quenching measurements have been made for a series of di-walled and tetra-walled molecular umbrellas having moderate (i.e., hydroxyl-) and strong (i.e., sulfate-) facial hydrophilicity, using Cascade Blue as the fluorophore. Through the use of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphotempocholine, 1-palmitoyl-2-stearoyl-(5-DOXYL)-sn-glycero-3-phosphocholine, and 1-palmitoyl-2-stearoyl-(12-DOXYL)-sn-glycero-3-phosphocholine as fluorescence quenchers, evidence has been obtained for a ...[more]

PMID: 18783220

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