Surface dielectric constant, surface hydrophobicity and membrane fusion

SummaryMembrane fusion induced by ions and its associated membrane property, surface dielectric constant, were studied with the use of acidic and neutral phospholipid vesicles. The fusion of vesicles was monitored by utilizing two fluorescence fusion assays: fluorescence content mixing method and fluorescence labelled membrane component dilution method. For the surface dielectric constant measurements, a fluorescence method was used which detected the environmental effect on the membrane surface upon the addition of various fusogenic cations. Also, the effects of poly-(ethylene glycol) on both fusion and surface dielectric properties were examined. It was found that the extent of fusion correlated well with the degree of lowering in the dielectric constant of the surface membrane, which corresponds to the increase in hydrophobicity of the membrane surface. This agrees with the previously obtained experimental results that the increase in interfacial tension of the membrane, which also corresponds to the increase in surface hydrophobicity, correlates with the extent of membrane fusion.

[1]  S. Marčelja,et al.  Repulsion of interfaces due to boundary water , 1976 .

[2]  L. Stryer,et al.  Fluorescent probes of biological membranes. , 1970, Proceedings of the National Academy of Sciences of the United States of America.

[3]  S. Ohki.  A mechanism of divalent ion-induced phosphatidylserine membrane fusion. , 1982, Biochimica et biophysica acta.

[4]  D. Hoekstra.  Role of lipid phase separations and membrane hydration in phospholipid vesicle fusion. , 1982, Biochemistry.

[5]  A. Herrmann,et al.  Water-Mediated Effects of PEG on Membrane Properties and Fusion , 1988 .

[6]  D. Hoekstra,et al.  Use of resonance energy transfer to monitor membrane fusion. , 1981, Biochemistry.

[7]  S. Ohki.  Surface Tension, Hydration Energy and Membrane Fusion , 1988 .

[8]  K. Arnold,et al.  Molecular Mechanisms of Membrane Fusion , 1988, Springer US.

[9]  V. Parsegian,et al.  Measurement of forces between lecithin bilayers , 1976, Nature.

[10]  W. Pangborn,et al.  Studies on the mechanism of membrane fusion: evidence for an intermembrane Ca2+-phospholipid complex, synergism with Mg2+, and inhibition by spectrin. , 1979, Biochemistry.

[11]  D. Papahadjopoulos,et al.  Intermembrane contact affects calcium binding to phospholipid vesicles. , 1982, Proceedings of the National Academy of Sciences of the United States of America.

[12]  N. Mataga,et al.  The Solvent Effect on Fluorescence Spectrum, Change of Solute-Solvent Interaction during the Lifetime of Excited Solute Molecule , 1955 .

[13]  H. Ohshima,et al.  Divalent cation-induced surface tension increase in acidic phospholipid membranes: Ion binding and membrane fusion , 1984 .

[14]  N. Düzgüneş,et al.  Calcium-induced interaction of phospholipid vesicles and bilayer lipid membranes. , 1977, Biochimica et biophysica acta.

[15]  S. Ohki,et al.  Effects of cations and polyamines on the aggregation and fusion of phosphatidylserine membranes. , 1986, Biochimica et biophysica acta.

[16]  O. Zschörnig,et al.  Effect of Peg on the Electrophoretic Mobility of Liposomes , 1987 .

[17]  B. Lentz,et al.  Rate and extent of poly(ethylene glycol)-induced large vesicle fusion monitored by bilayer and internal contents mixing. , 1986, Biochemistry.

[18]  A. Herrmann,et al.  The dielectric properties of aqueous solutions of poly(ethylene glycol) and their influence on membrane structure. , 1985, Biochimica et biophysica acta.

[19]  E. G. Finer,et al.  Crystalline anhydrous Ca-phosphatidylserine bilayers. , 1977, Biochemical and biophysical research communications.

[20]  R. Macdonald,et al.  Membrane fusion due to dehydration by polyethylene glycol, dextran, or sucrose. , 1985, Biochemistry.

[21]  Y. Kimura,et al.  Local dielectric properties around polar region of lipid bilayer membranes , 2005, The Journal of Membrane Biology.

[22]  H. Rasmussen.  Cell Communication, Calcium Ion, and Cyclic Adenosine Monophosphate , 1970, Science.

[23]  E. Lippert,et al.  Spektroskopische Bestimmung des Dipolmomentes aromatischer Verbindungen im ersten angeregten Singulettzustand , 1957, Zeitschrift für Elektrochemie, Berichte der Bunsengesellschaft für physikalische Chemie.

[24]  P. C. Hiemenz,et al.  Principles of colloid and surface chemistry , 1977 .

[25]  D. Papahadjopoulos,et al.  Ca2+-induced fusion of phospholipid vesicles monitored by mixing of aqueous contents , 1979, Nature.

[26]  G. Feigenson.  On the nature of calcium ion binding between phosphatidylserine lamellae. , 1986, Biochemistry.