Abstract
Upon periodical bending of a BLM, by means of oscillating hydrostatic pressure with sound frequency, the generation of an a.c. electric current with the same frequency can be observed under short circuit conditions. Previously, this phenomenon was attributed by us to a displacement current due to the oscillating flexoelectric polarization. The latter is proportional to the membrane curvature and depends on the lipid dipole moment and surface charge.
The theory of this effect is outlined here. Earlier results concerning dipolar and quadrupolar contributions to the total current are presented and new expressions about charge contributions are derived for the two basic regimes of free and blocked lateral lipid exchange.
Further, a systematic study of the frequency dependence of the amplitude and phase of the curvature-electric signal from a bacterial phosphatidylethanolamine/n-decane BLM is reported. Constant membrane curvature at each vibration frequency was assured by a calibration of the capacitance current observed with a small transmembrane voltage.
The frequency dependence of the curvature-electric current amplitude was characterized by two regions: low frequency plateau and high frequency slope, the boundary between them being about 160 Hz. Such behaviour suggested a switching of the mechanism of membrane polarization from free to blocked lateral lipid exchange. Frequency dependence of the phase shift was characterized by low frequency and high frequency plateaus and a gradual transition between them. From phase measurements on initially curved membranes the sign of the membrane flexo-coefficient was found to be negative.
The influence of some modifiers of the surface charge and surface dipole, as well as of the membrane conductivity, upon the value of the effect was studied. Surface charge was separately measured by the internal field compensation method under an ionic strength gradient. The membrane flexoelectric coefficient was evaluated and compared to the theoretical predictions. A conclusion was drawn that under the present experimental conditions the main contribution to the effect comes from the curvatureinduced shift of the surface charge equilibrium.
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References
Andersen OS, Finkelstain A, Katz I, Cass A (1976) Effect of phloretin on the permeability of thin lipid membranes. J Gen Physiol 67: 749–771
Bivas I, Petrov AG (1981) Flexoelectric and steric interactions between two lipid bilayer membranes resulting from their curvature fluctuations. J Theor Biol 88: 459–483
Cherni VV, Sokolov VS, Abidor IG (1980) Determination of surface charge of bilayer lipid membranes. Bioelectrochem Bioenerg 7: 413–420
Chizmadzhev YuA, Chernomordik LV, Pastushenko VF, Abidor IG (1982) Electrical breakdown of BLM. In: Kostyuk PG (ed) Biofizika membran, vol 2, VINITI, Moscow, pp 161–266
DeGennes PG (1974) The physics of liquid crystals. Claredon Press, Oxford
Derzhanski A, Petrov AG, Pavloff YV (1981) Curvatureinduced conductive and displacement currents through lipid bilayers. J Phys Lett (Paris) 42: L-119-L-122
Lis LJ, McAlister M, Fuller N, Rand RP, Parsegian VA (1982) Measurement of the lateral compressibility of several phospholipid bilayers. Biophys J 37: 667–672
Meyer RB (1969) Fiezoelectric effects in liquid crystals. Phys Rev Lett 22: 918–922
Ochs AL, Burton RM (1974) Electrical response to vibration of a lipid bilayer membrane. Biophys J 14: 473–489
Passechnik VI, Bichkova EJ (1978) Piezoeffect, background conductivity and filtration coefficients of bilayer lipid membranes. Biofizika (Moscow) 23: 551–552
Passechnik VI, Sokolov VS (1973) Permeability change of modified bimolecular phospholipid membranes accompanying periodical expansion. Biofizika (Moscow) 18: 655–660
Passechnik VI, Sokolov VS (1975) Mechanical oscillations of bilayer membranes. Biofizika (Moscow) 20: 743–744
Petrov AG (1975) Flexoelectric model for active transport. In: Physical and chemical bases of biological information transfer. Plenum Press, New York London, pp 111–125
Petrov AG (1977) Flexoelectric effects and transport phenomena in biomembranes. Fourth Winter School Biophys Membrane Transport, Poland, School Proceedings, Wroclaw, 3: 168–176
Petrov AG (1978) Mechanisms of curvature-induced membrane polarization and their influence on some membrane properties. Studia biophys 74: 51–52, Microfiche 4/pp 14–25
Petrov AG (1984) Flexoelectricity of lyotropics and biomembranes. Nuovo Cimento 3D: 174–192
Petrov AG, Bivas I (1984) Elastic and flexolelectric aspects of out-of-plane fluctuations in biological and model membranes. Prog Surf Sci 16: 389–512
Petrov AG, Derzhanski A (1976) On some problems in the theory of elastic and flexoelectric effects in bilayer lipid membranes and biomembranes. J Phys (Paris) (Suppl) 37: C3-155–C3-160
Petrov AG, Pavloff YV (1979) A new model for flexoelectric polarization of bilayer lipid membranes at blocked “flip-flop”. J Phys (Paris) (Suppl) 40: C3-455–C3-457
Petrov AG, Tverdislov VA, Derzhanski A (1978) Flexoelectric aspects of lipid-protein interaction in biomembranes. Ann Phys (Paris) 3: 273–274
Petrov AG, Seleznev SA, Derzhanski A (1979) Principles and methods of liquid crystal physics applied to the structure and functions of biological membranes. Acta Phys Pol A 55: 385–405
Seleznev SA, Petrov AG (1983) Short and long-range interactions between proteins and mesomorphic lipids within biological membranes. CR Acad Bulg Sci 36: 615–618
Shipley GG (1973) Recent X-ray diffraction studies of biological membranes and membrane components.In: Chapman D, Wallach DFH (eds) Biological membranes, vol 2. Academic Press, London, pp 1–89
Sokolov VS (1982) Investigation of charge transfer mechanism through a membrane, induced by nigericin and grisorixin antibiotics. PhD Thesis, Moscow State University
Sokolov VS, Cherni VV, Markin VS (1984) Measurement of the dipolar potential jumps at the adsorption of phloretin on the BLM surface by the inner field compensation method. Biofizika (Moscow) 24: 424–429
Standish MM, Pethica BA (1968) Surface pressure and surface potential study of a synthetic phospholipid at the air/water interface. Trans Faraday Soc 64: 1113–1122
Szekely JG, Morash BD (1980) The effect of temperature on capacitance changes in an oscillating model membrane. Biochim Biophys Acta 599: 73–80
Taupin C, Dvolaitzky M, Sauterey C (1975) Osmotic pressure induced pores in phospholipid vesicles. Biochemistry 14: 4771–4775
Vaidhyanathan VS (1982) Inhomogeneous interfacial regions near a cell surface. Studia biophys 90: 37–46
Vaidhyanathan VS (1983) ADO and additional comments on the inhomogeneous regions,near a biological membrane. 7th Int Symp Bioelectrochemistry, Stuttgart, FRG
Wobschall D (1971) Bilayer membrane elasticity and dynamic response. J Colloid Interface Sci 36: 385–396
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Petrov, A.G., Sokolov, V.S. Curvature-electric effect in black lipid membranes. Eur Biophys J 13, 139–155 (1986). https://doi.org/10.1007/BF00542559
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DOI: https://doi.org/10.1007/BF00542559