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2 H NMR of oriented phospholipid/cholesterol bilayers containing an amphiphilic peptide. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183196. [DOI: 10.1016/j.bbamem.2020.183196] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 12/17/2019] [Accepted: 01/10/2020] [Indexed: 10/25/2022]
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Turnbull D, Spaepen F. Crystal nucleation and the crystalmelt interfacial tension in linear hydrocarbons. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/polc.5070630120] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Loudet C, Manet S, Gineste S, Oda R, Achard MF, Dufourc EJ. Biphenyl bicelle disks align perpendicular to magnetic fields on large temperature scales: a study combining synthesis, solid-state NMR, TEM, and SAXS. Biophys J 2007; 92:3949-59. [PMID: 17307824 PMCID: PMC1868983 DOI: 10.1529/biophysj.106.097758] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A phosphatidylcholine lipid (PC) containing a biphenyl group in one of its acyl chains (1-tetradecanoyl-2-(4-(4-biphenyl)butanoyl)-sn-glycero-3-PC, TBBPC) was successfully synthesized with high yield. Water mixtures of TBBPC with a short-chain C(6) lipid, dicaproyl-PC (DCPC), lead to bicelle systems formation. Freeze-fracture electron microscopy evidenced the presence of flat bilayered disks of 800 A diameter for adequate composition, hydration, and temperature conditions. Because of the presence of the biphenyl group, which confers to the molecule a positive magnetic anisotropy Delta chi, the disks align with their normal, n, parallel to the magnetic field B(0), as directly detected by (31)P, (14)N, (2)H solid-state NMR and also using small-angle x-ray scattering after annealing in the field. Temperature-composition and temperature-hydration diagrams were established. Domains where disks of TBBPC/DCPC align with their normal parallel to the field were compared to chain-saturated lipid bicelles made of DMPC(dimyristoylPC)/DCPC, which orient with their normal perpendicular to B(0). TBBPC/DCPC bicelles exist on a narrow range of long- versus short-chain lipid ratios (3%) but over a large temperature span around room temperature (10-75 degrees C), whereas DMPC/DCPC bicelles exhibit the reverse situation, i.e., large compositional range (22%) and narrow temperature span (25-45 degrees C). The two types of bicelles present orienting properties up to 95% dilution but with the peculiarity that water trapped in biphenyl bicelles exhibits ordering properties twice as large as those observed in the saturated-chains analog, which offers very interesting properties for structural studies on hydrophilic or hydrophobic embedded biomolecules.
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Affiliation(s)
- Cécile Loudet
- UMR 5248 CBMN, CNRS-Université Bordeaux 1-ENITAB, Institut Européen de Chimie et Biologie, Pessac, France
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Diehl P, Reinhold M, Tracey A, Wullschleger E. An interpretation of the anomalous results from a nuclear magnetic resonance study of13C-methanol partially oriented in nematic liquid crystalline phases. Mol Phys 2006. [DOI: 10.1080/00268977500103281] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Luckhurst G, Poupko R, Zannoni C. Spin relaxation for biradical spin probes in anisotropic environments. Mol Phys 2006. [DOI: 10.1080/00268977500102091] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- G.R. Luckhurst
- a Department of Chemistry , The University , Southampton , SO9 5NH
| | - R. Poupko
- a Department of Chemistry , The University , Southampton , SO9 5NH
- b The Weizmann Institute of Science , Rehovot , Israel
| | - C. Zannoni
- a Department of Chemistry , The University , Southampton , SO9 5NH
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7
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Wong TC, Jeffrey KR. Molecular motion in a magnetically aligned lyotropic liquid crystal system. Mol Phys 2006. [DOI: 10.1080/00268978200101021] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Tuck C. Wong
- a Department of Chemistry , University of Missouri , Columbia , Missouri , 65211 , U.S.A
| | - Kenneth R. Jeffrey
- b Department of Physics , University of Guelph , Guelph , Ontario , Canada , N1G 2W1
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Rice DM, Meadows MD, Scheinman AO, Goni FM, Gomez JC, Moscarello MA, Chapman D, Oldfield E. Protein-lipid interactions. A nuclear magnetic resonance study of sarcoplasmic reticulum (calcium(2+), magnesium(2+) ion)-activated ATPase, lipophilin, and proteolipid apoprotein-lecithin systems and a comparison with the effects of cholesterol. Biochemistry 2002. [DOI: 10.1021/bi00593a021] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Crowell KJ, Macdonald PM. Surface charge response of the phosphatidylcholine head group in bilayered micelles from phosphorus and deuterium nuclear magnetic resonance. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1416:21-30. [PMID: 9889304 DOI: 10.1016/s0005-2736(98)00206-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Solid-state phosphorus (31P) and deuterium (2H) nuclear magnetic resonance (NMR) spectroscopy over the temperature range of 25-50 degreesC were used to investigate bilayered micelles (bicelles) composed of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and 1, 2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC) in the presence of either the anionic lipid 1,2-dimyristoyl-sn-3-phosphoglycerol (DMPG) or the cationic lipid 1,2-dimyristoyl-3-trimethylammonium-propane (DMTAP). The 31P-NMR spectra demonstrate that bicellar structures form with DMPG/DMPC ratios ranging from 0 to 50/50 and with DMTAP/DMPC ratios from 0 to 40/60, while the overall concentration of DHPC remains constant. The formation of bicelles containing charged amphiphiles is contingent upon the presence of NaCl, with 50 mM NaCl being sufficient for bicelle formation at all concentrations of charged amphiphile investigated, while 150 mM NaCl affords better resolution of the various 31P-NMR resonance signals. The 2H-NMR spectra demonstrate that the quadrupolar splittings (Deltanu) of head group-deuterated DMPC change inversely as a function of the amount of negative versus positive charge present, and that the changes for deuterons on the alpha-carbon are opposite in sense to those for deuterons on the beta-carbon. This indicates that head group-deuterated phosphatidylcholine functions as a molecular voltmeter in bicelles in much the same fashion as it does in spherical vesicles.
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Affiliation(s)
- K J Crowell
- Department of Chemistry, University of Toronto at Mississauga, 3359 Mississauga Road, Mississauga, Ont. L5L 1A2, Canada
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Das P, Schwarz WH. Solitons in cell membranes. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1995; 51:3588-3612. [PMID: 9963042 DOI: 10.1103/physreve.51.3588] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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11
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Kumar B, Ramanathan K, Khetrapal C, Opellaz S, Becker ED. Determination of the sign of the order parameter from MAS spectra of oriented molecules. ACTA ACUST UNITED AC 1990. [DOI: 10.1016/0022-2364(90)90029-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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12
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Delikatny E, Burnell E. Determination of the complete order matrix of the alpha methylene segment of potassium palmitate. Mol Phys 1989. [DOI: 10.1080/00268978900101431] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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13
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Charvolin J. Lyotropic Liquid Crystals, Structures and Phase Transitions. PHASE TRANSITIONS IN SOFT CONDENSED MATTER 1989. [DOI: 10.1007/978-1-4613-0551-4_10] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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14
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An X-ray and NMR investigation of the lamellar liquid crystalline phase in the octylamine/octylammonium chloride/water system. J Colloid Interface Sci 1987. [DOI: 10.1016/0021-9797(87)90452-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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15
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Lamellar liquid crystal and other phases in the system sodium dodecyl sulfate, hexylamine, water, and heptane. J Colloid Interface Sci 1987. [DOI: 10.1016/0021-9797(87)90405-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Charvolin J. Aggregates of amphiphilic molecules in lyotropic liquid crystals. ACTA ACUST UNITED AC 1984. [DOI: 10.1007/bf02452198] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Canet D, Marchal J, Nery H, Robin-Lherbier B, Cases J. Nuclear magnetic resonance studies of alkylammonium chlorides in aqueous solution. II. Carbon-13 longitudinal relaxation times and nuclear overhauser enhancements in isotropic micellar media and in the lamellar mesophase. J Colloid Interface Sci 1983. [DOI: 10.1016/0021-9797(83)90402-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Davis JH. The description of membrane lipid conformation, order and dynamics by 2H-NMR. BIOCHIMICA ET BIOPHYSICA ACTA 1983; 737:117-71. [PMID: 6337629 DOI: 10.1016/0304-4157(83)90015-1] [Citation(s) in RCA: 739] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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20
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Rondelez F, Koppel D, Sadashiva B. Two-dimensional films of discotic molecules at an air-water interface. ACTA ACUST UNITED AC 1982. [DOI: 10.1051/jphys:019820043090137100] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Meraldi JP, Schlitter J. A statistical mechanical treatment of fatty acyl chain order in phospholipid bilayers and correlation with experimental data. B. Dipalmitoyl-3-sn-phosphatidylcholine. BIOCHIMICA ET BIOPHYSICA ACTA 1981; 645:193-210. [PMID: 6895036 DOI: 10.1016/0005-2736(81)90190-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In order to help bridge the conceptual gap between experimental data on chains of phospholipid molecules and their microscopic organization, a theoretical model has proposed in a preceding paper. The intentions associated with the new theory were to describe a model able to reproduce accurately the experimental data. This capability is essential to monitor some of the mechanisms behind the physical data. The results presented here show first that, provided a suitable fitting of the phenomenological parameters entailed in the model, the theory indeed gives good agreement with experimental data (2H-NMR, neutron scattering, calorimetry) obtained for a dipalmitoyl-3-sn-phosphatidylcholine bilayer. This property of the model is then specifically used to describe the nature of the perturbing effects of local anaesthetics and cholesterol on the organization of the acyl chains and to correlate these effects with the experimental data. Finally the theoretical model is used to supplement experimental data by describing the acyl chain organization in terms of the most probable spectrum of chain conformations. Predictions are made about the one-, two- and three-dimensional mean spatial characteristics of the acyl chains.
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22
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Direct determination of the oriented sample nmr spectrum from the powder spectrum for systems with local axial symmetry. Chem Phys Lett 1981. [DOI: 10.1016/0009-2614(81)80089-9] [Citation(s) in RCA: 162] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Kinsey R, Kintanar A, Tsai M, Smith R, Janes N, Oldfield E. First observation of amino acid side chain dynamics in membrane proteins using high field deuterium nuclear magnetic resonance spectroscopy. J Biol Chem 1981. [DOI: 10.1016/s0021-9258(19)69407-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Quinn PJ. The fluidity of cell membranes and its regulation. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 1981; 38:1-104. [PMID: 7025092 DOI: 10.1016/0079-6107(81)90011-0] [Citation(s) in RCA: 237] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Abstract
Membranes are the most common cellular structures in both plants and animals. They are now recognized as being involved in almost all aspects of cellular activity ranging from motility and food entrapment in simple unicellular organisms, to energy transduction, immunorecognition, nerve conduction and biosynthesis in plants and higher organisms. This functional diversity is reflected in the wide variety of lipids and particularly of proteins that compose different membranes. An understanding of the physical principles that govern the molecular organization of membranes is essential for an understanding of their physiological roles sincestructureandfunctionare much more interdependent in membranes than in, say, simple chemical reactions in solution. We must recognize, however, that the word ‘understanding’ means different things in different disciplines, and nowhere is this more apparent than in this multidisciplinary area where biology, chemistry and physics meet.
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Abstract
The membranes of living organisms are involved in many aspects of the life, growth and development of all cells. The predominant structural elements of these membranes are lipids and proteins and the basic strucvture of these molecules has been reviewed. The physical properties of the lipid constituents particularly their behavior in aqueous systems has led to the concepts of thermotropic and lyotropic mesomorphism; the interaction between different types of lipid molecules modulate this behavior. Interaction of phospholipids in aqueous systems with cholesterol, ions and drugs have been examined in this context. In addition a variety of model lipid-protein systems have been investigated and the implications of interactions between lipids and different proteins in biological membranes has been evaluated. This leads to a detailed consideration of the way lipids and proteins ae organized in cell membranes and contains an appraisal of the evidence supporting contemporary views of membrane structure. Particular attention has been devoted to the question of how mobile the components are within the structure. Particular attention has been devoted to the question of how mobile the components are within the structure. Finally the biosynthesis, turnover and modulation of the properties of interacting membrane constituents is critically reviewed and possible ways of controlling the behavior of cells and organisms by altering the structural parameters of different membranes has been considered.
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Molecular motion in the lyotropic liquid crystal system containing potassium palmitate: A study of proton spin-lattice relaxation times. ACTA ACUST UNITED AC 1979. [DOI: 10.1016/0022-2364(79)90090-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Turner GL, Oldfield E. Effect of a local anaesthetic on hydrocarbon chain order in membranes. Nature 1979; 277:669-70. [PMID: 423968 DOI: 10.1038/277669a0] [Citation(s) in RCA: 68] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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32
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Charvolin J, Levelut A, Samulski E. Lyotropic nematics : molecular aggregation and susceptibilities. ACTA ACUST UNITED AC 1979. [DOI: 10.1051/jphyslet:019790040022058700] [Citation(s) in RCA: 119] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Hsi S, Zimmermann H, Luz Z. Deuterium magnetic resonance of some polymorphic liquid crystals: The conformation of the aliphatic end chains. J Chem Phys 1978. [DOI: 10.1063/1.437092] [Citation(s) in RCA: 89] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Seelig J, Waespe-Sarcevic N. Molecular order in cis and trans unsaturated phospholipid bilayers. Biochemistry 1978; 17:3310-5. [PMID: 687586 DOI: 10.1021/bi00609a021] [Citation(s) in RCA: 314] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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35
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Davis J, Jeffrey K, Bloom M. Spin-lattice relaxation as a function of chain position in perdeuterated potassium palmitate. ACTA ACUST UNITED AC 1978. [DOI: 10.1016/0022-2364(78)90144-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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NMR Studies of Model Biological Membrane Systems: Unsonicated Surfactant-Water Dispersions. ACTA ACUST UNITED AC 1978. [DOI: 10.1016/b978-0-12-571812-7.50007-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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38
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Abdolall K, Burnell E, Valic M. The temperature dependence of water and counter ion order in soap-water mesophases. A deuterium and sodium NMR study. Chem Phys Lipids 1977. [DOI: 10.1016/0009-3084(77)90085-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Higgs T, Mackay A. Determination of the complete order parameter tensor for a lipid methylene group from 1H- and 2H-NMR spin labels. Chem Phys Lipids 1977. [DOI: 10.1016/0009-3084(77)90084-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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40
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Davis J, Jeffrey K. The temperature dependence of chain disorder in potassium palmitate-water. A deuterium NMR study. Chem Phys Lipids 1977. [DOI: 10.1016/0009-3084(77)90083-4] [Citation(s) in RCA: 65] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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41
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Abstract
Proton and carbon-13 nmr spectra of unsonicated lipid bilayers and biological membranes are generally dominated by strong proton–proton and proton–carbon dipolar interactions. As a result the spectra contain a large number of overlapping resonances and are rather difficult to analyse. Nevertheless, important information on the structure and dynamic behaviour of lipid systems has been provided by these techniques (Wennerström & Lindblom, 1977).
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Huang C. Configurations of fatty acyl chains in egg phosphatidylcholine-cholesterol mixed bilayers. Chem Phys Lipids 1977; 19:150-8. [PMID: 880729 DOI: 10.1016/0009-3084(77)90095-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Based on the structural properties of cholesterol and egg phosphatidylcholine, and on the assumption that the van der Waals' type attactive interaction between the steroid nucleus and the fatty acyl chains provides a stabilizing force for the cholesterol-egg phosphatidylcholine complex, some specific orientation and configurations of the fatty acyl chains around the steroid nucleus in the interacting system are proposed in terms of an optimal packing. The proposed model suggests thathe saturated chains are largely facing the flattened (alpha) surface of the steroid nucleus of cholesterol, while the unsaturated chains can interact with both the alpha and beta surfaces of the steroid nucleus. It is also suggested that the angular methyl groups on the beta surface of the steroid nucleus lock the unsaturated fatty acyl chain in a relatively immobile configuration. Experimental evidence which provides support for the proposed stereochemical model is presented.
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Banville M, Caillé A, Zuckermann MJ. Interface dipolar plasmons in liquid multilayer structures. J Chem Phys 1977. [DOI: 10.1063/1.434401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Huang CH. A structural model for the cholesterol-phosphatidylcholine complexes in bilayer membranes. Lipids 1977; 12:348-56. [PMID: 558491 DOI: 10.1007/bf02533637] [Citation(s) in RCA: 172] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Based on the structural properties of phospholipid and cholesterol molecules, and making use of the known structural and motional effects of cholesterol and its analogs on phospholipid bilayers, a model for the cholesterol-phosphatidylcholine complex is proposed. In this model, the 3beta-hydroxyl group of cholesterol is assumed to engage in hydrogen bonding with the carbonyl oxygen of the fatty acyl groups in phospholipids. Some specific configurations of the saturated and unsaturated fatty acyl chains of the phospholipid are suggested to participate in van der Waals attractive interactions with the apha and beta surface of the steroid nucleus.
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Seelig A, Seelig J. Effect of a single cis double bond on the structures of a phospholipid bilayer. Biochemistry 1977; 16:45-50. [PMID: 831777 DOI: 10.1021/bi00620a008] [Citation(s) in RCA: 222] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The ordering of the hydrocarbon chains and the rates of lipid motion are two independent parameters characterizing the structure and the dynamics, respectively, of a bilayer membrane. In this work, deuterium magnetic resonance has been used to elucidate the influence of a single cis double bond on the hydrocarbon chain ordering of a phospholipid bilayer. 1-Palmitoyl-2-oleoyl-3-sn-phosphatidylcholine was specifically deuterated at various segments of the palmitic acyl chain and at the 9, 10 position of the oleic acyl chain, and the segmental order parameters were deduced from the quadrupole splittings of the unsonicated bilayer phases. The shape of the order profile of the palmitic acyl chain is similar to that observed for the corresponding fully saturated membrane, but the magnitude of the order parameters is distinctly smaller in the unsaturated system. This demonstrates that the presence of a double bond in a membrane causes a more disordered conformation of the hydrocarbon chains. Considering the relative flexibility within the palmitic acyl chain, the deuterium resonance data indicate a local stiffening of those segments which are located in the vicinity of the double bond. The membrane fluidity was investigated using a nitroxide-labeled stearic acid spin probe. The smaller electron paramagnetic resonance line width in bilayers of 1-palmitoyl-2-oleoyl-3-sn-phosphatidylcholine demonstrates an increased fluidity compared to bilayers of 1,2-dipalmitoyl-3-sn-phosphatidylcholine.
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Abstract
The present status of the spin labeling method as applied to Biophysics is examined. After an outline of the chemical and physical properties of NO radicals, the analysis of linear and non-linear ESR spectra of spin labels and the information it yields is described. The possibilities of the method are critically discussed in the light of recent experiments.
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Seelig J, Gally H. Investigation of phosphatidylethanolamine bilayers by deuterium and phosphorus-31 nuclear magnetic resonance. Biochemistry 1976; 15:5199-204. [PMID: 11810 DOI: 10.1021/bi00669a001] [Citation(s) in RCA: 153] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The motion of the ethanolamine head group in unsonicated lipid bilayers above and below the phase transition is studied by means of deuterium and phosphorus magnetic resonance. For this purpose, dipalmitoyl-3-sn-phosphatidylethanolamine is selectively deuterated at the two ethanolamine carbon atoms. The deuterium quadrupole splittings of the corresponding bilayer phases are measured at pH 5.5 as a function of temperature. In addition, the phosphorus-31 chemical shift anisotropies of planor-oriented and randomly dispersed samples of dipalmitoyl-3-sn-phosphatidylethanolamine are measured at pH 5.5 and 11 by applying a proton-decoupling field. The knowledge of the static chemical shift tensor (Kohler, S.J., and Klein, M.P. (1976), Biochemistry 15, 967) provides the basis for a quantitive analysis of the head-group motion. The nuclear magnetic resonance data are consistent with a model in which the ethanolamine group is rotating flat on the surface of the bilayer with rapid transitions occurring between two enantiomeric conformations.
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Boden N, Jackson P, Levine YK, Ward AJ. Intramolecular disorder and its relation to mesophase structure in lipid/water mixtures. BIOCHIMICA ET BIOPHYSICA ACTA 1976; 419:395-403. [PMID: 1247567 DOI: 10.1016/0005-2736(76)90253-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
NMR spin-half pair dipolar echo measurements are reported for the lamellar (dispersions and multibilayer stacks) and hexagonal phases of potassium palmitate/2H2O mixtures. In the lamellar Lbeta and Lgamma (gel) phases the alkyl chains are rigid and perfectly ordered, while in the lamellar Lalpha and hexagonal phases they are flexible and disordered. In particular, the measurements show that in the fluid lamellar Lalpha phase the chain is "bent" at the C9-C10 segment; but is "straight" in the hexagonal phase.
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