摘要(英) |
We investigate two-component membranes composed of POPE and POPC, and three-component membranes composed of POPE, POPC and sterol. The phase behavior of POPC/POPE membranes was studied as a function of POPE concentration and temperature by 2H-NMR and DSC. For 2H-NMR measurements, POPC and POPE were deuterium labeled alternatively such that the behavior of both POPC and POPE can be observed. We present the first temperature-composition diagram for POPE concentration range from 0 to 60 mol%. Coexistence of the gel and lc phases is observed over a wide temperature and composition range. It is found that POPC and POPE do not mix well in 1:1 POPC/POPE below17℃, but mix well above 17℃.
To investigate the properties of POPC/POPE membranes in the presence of sterol, 1:1:1 POPC/POPE/ergosterol and 1:1:1 POPC/POPE/cholesterol were studied as a function of temperature by 2H-NMR, with POPC and POPE deuterium labeled alternatively. We show that the presence of ergosterol (or cholesterol) disorders gel-phase POPC/POPE (1:1) membranes, whereas orders lc-phase POPC /POPE (1:1) membranes. The effect of ergosterol is weaker than cholesterol. Furthermore, the presence of ergosterol (or cholesterol) modulates the mixing properties of POPC/POPE membranes. POPC and POPE mix well in some temperature range, where they are poorly mixed in the absence of sterol. The enhancement of mixing of of POPC/POPE membranes by ergosterol is observed in a temperature range narrower than that by cholesterol. |
參考文獻 |
Reference
[1]. Molecular Biology of the Cell. Third edition. Bruce Alberts et al. Chapter 10 Membrane Structure.
[2]. Pieter R. Cullis, Michael J. Hope, and Colin P.S. Tilcock. 1986. Lipid polymorphism and the roles of lipids in membranes. Chemistry and Physics of lipids. 40:127-144.
[3]. Bazzi MD, Youakim MA, and Nelsestuen GL. 1992. Importance of phosphatidylethanolamine for association of protein kinase C and other cytoplasmic proteins with membranes. Biochemistry. 31:1125-34.
[4]. Roger Schneiter, Britta Brügger, and Roger Sandhoff. 1999. Electrospray Ionization Tandem Mass Spectrometry (ESI-MS/MS) Analysis of the Lipid Molecular Species Composition of Yeast Subcellular Membranes Reveals Acyl Chain-based Sorting/Remodeling of Distinct Molecular Species En Route to the Plasma Membrane. The Journal of Cell Biology. 146:741-754.
[5]. Georg Pabst, Michael Rappolt, and Heinz Amenitsch. 2000. X-ray Kinematography of Temperature-Jump Relaxation Probes the Elastic Properties of Fluid Bilayers. Langmuir 16:8994-1378.
[6]. Paul E. Harper, David A. Mannock, and Ruthven N. A. Lewis. 2001. X-Ray Diffraction Structures of Some Phosphatidylethanolamine Lamellar and Inverted Hexagonal Phases. Biophysical J. 81:2693-2706.
[7]. Robin L. Thurmond, Steven W. Dodd, and Michael F. Brown. 1991. Molecular areas of phospholipids as determined by 2H NMR spectroscopy. Biophys. J. 59:108-113.
[8]. Marsh, D., A. Watts, and I. C. P. Smith. 1983. Dynamic structure and phase behavior of dimyristoylphosphatidylethanolamine bilayers studied by deuterium nuclear magnetic resonance. Biochemistry. 22:3023-3026.
[9]. Òscar Doménech, Juan Torrent-Burgues, Sandra Merino. 2005. Surface thermodynamics study of monolayer formed with heteroacid phospholipids of biological interest. Colloids and Surfaces B. 41:233-238.
[10]. Chantal Paré and Michel Lafleur. 1988. Polymorphism of POPE/Cholesterol System: A 2H Nuclear Magnetic Resonance and Infrared Spectroscopic Investigation. Biophysics Journal. 74:889-909.
[11]. Ya-Wei Hsueh, Kyle Gilbert, and C. Trandum. 2005. The effect of ergosterol on dipalmitoylphosphatidylcholine bilayer: a deuterium NMR and calorimetric study. Biophysical Journal. 88:1799-1808.
[12]. Julio A. Urbina, Sara Pekerar, and Hong-biao Le. 1995. Molecular order and dynamics of phosphatidylcholine bilayer membranes in the presence of cholesterol, ergosterol and lanosterol: a comparative study using 2H-, 13C- and 31P-NMR spectroscopy. Biochimica et Biophysica Acta. 1238:163-176.
[13]. Bogdanov M and Dowhan W. 1995. Phosphatidylethanolamine is required for in vivo function of the membrane-associated lactose permease of Escherichia coli. J Biol Chem. 270:732-9.
[14]. Brian Cannon, Martin Hermansson, and sandor Györke. 2003. Regulation of calcium channel activity by lipid domain formation in planar lipid bilayers. Biophysical J. 85:933-942.
[15]. Brian Cannon, Anthony Lewis, and Jennifer Metze. 2006. Cholesterol Supports Headgroup Superlattice Domain Formation in Fluid Phospholipid/Cholesterol Bilayers. J. Phus. Chem. B. 110:6339-6350.
[16]. Kwan Hon Cheng, Mika Ruonala, and Jorma Virtanen. 1997. Evidence for superlattice arrangements in fluid phosphatidylcholine/phosphatidylethanolamine bilayers. Biophysical J. 73:1967-1976.
[17]. Omar Bakht, Priyadarshini Pathak, and Erwin London. 2007. Effect of the Structure of Lipids Favoring Disordered Domain Formation on the Stability of Cholesterol-Containing Ordered Domains (Lipid Rafts): Identification of Multiple Raft-Stabilization Mechanisms. Biophysical Journal. 93:4307-4318.
[18]. Sarah L. and Sarah L. Keller. 2003. Separation of Liquid Phases in Giant Vesicles of Ternary Mixtures of Phospholipids and Cholesterol. Biophysical J. 85:3074-3083.
[19]. Sarah L. and Sarah L. Keller. 2005. Miscibility Phase Diagrams of Giant Vesicles Containing Sphingomyelin. P. R. L. 94:148101.
[20]. M. Lafleur, P. R. Cullis, and M. Bloom. 1990. Modulation of the orientational order profile of the lipid acyl chain in the Lα phase. Eur. Biophys. J. 19:55-62.
[21]. L. J. Burnett and B. H. Muller. 1971. Deuteron quadrupole coupling constants in three solid deuterated paraffin hydrocarbons: C2D6, C4D10, C6D14. J. Chem. Phys. 55: 5829-5831.
[22]. Meraldi JP and Schlitter J. 1981. A statistical mechanical treatment of fatty acyl chain order in phospholipid bilayers and correlation with experimental data. B. Dipalmitoyl-3-sn-phosphatidylcholine. Biochim Biophys Acta. 645:193-210.
[23]. Davis, J. H., K. R. Jeffrey, M. Bloom, M. I. Valic, and T. P. Higgs. 1976. Quadrupolar echo deuteron magnetic resonance spectroscopy in ordered hydrocarbon chains. Chem. Phys. Lett. 42:390-394.
[24]. Lafleur, M., B. Fine, and E. Sternin. 1989. Smoothed orientational order profile of lipid bilayers by 2H-nuclear magnetic resonance. Biophys. J. 56:1037-1041.
[25]. Bruno Perly, Ian C. P. Smith, and Harold C. Jarrell. 1985. Effect of the replacement of a double bond by a cyclopropane ring in phosphatidylethanolamines: a 2H-NMR study of phase transitions and molecular organization. Biochemistry. 24:1005-1063.
[26]. Xin-Min Li, Maureen M. Momsen, and Howard L. Brockman. 2003. Sterol Structure and Sphingomyelin Acyl Chain Length Modulate Lateral Packing Elasticity and Detergent Solubility in Model Membranes. Biophysical Journal. 85:3788-3801.
[27]. J. Henriksen, A. C. Rowat, E Brief, and Y. W. Hsueh. 2006. Universal Behavior of Membranes with Sterols. Biophysical Journal. 90:1639-1649.
[28]. Ya-Wei Hsueh, Mei-Ting Chen, and Philipus J. Patty. 2007. Ergosterol in POPC membranes: physical properties and comparison with structurally similar sterols. Biophysical J. 92:1606-1615.
[29]. Tapas K. Ray, Vladimir P.Skipski, and Marion Barclay. 1969. Lipid Composition of Rat Liver Plasma Membranes. Biological Chemistry J. 244:5528-5536. |