Lecithin bilayer

Parsegian, V. A., Fuller, N., and Rand, R. P. (1979). Measured work of deformation and repulsion of lecithin bilayers, Proc. 

Totally synthetic bilayers show liquid crystalline properties similar to those of lecithin bilayers (Nagamura et al., 1978 Kano et al., 1979). Bilayer formation has also been observed for dialkyl compounds with anionic head groups such as [2] and [3] (Kunitake and Okahata, 1978a Mortara et al., 1978), and with nonionic and zwitterionic head groups as in [4] and [5] (Okahata et al., 1978a). 

M. Vincent and J. Gallay, Time-resolved fluorescence anisotropy study of effect of a cis double bond on structure of lecithin and cholesterol-lecithin bilayers using n-(9-anthroyloxy) fatty acids as probes, Biochemistry 23, 6514-6522 (1984). 

Wolosin, J.M., Ginsburg, H., Eieb, W.R., and Stein, W.D. Diffusion within egg lecithin bilayers resembles that within soft polymers, / Gen. Physiol, 71 93-100, 1978. 

Tab. 4.14 Permeability coefficients (Pm) for various non-electrolyte solutes across egg lecithin bilayer membranes at 25 °C. (Reprinted from Tab. 2 of ref. 49 with permission from Bertels-mann-Springer)...

Figure 1. Membrane capacitance and conductance of lecithin bilayers. Curve 1 membrane capacitance ((— X —) measured values at high frequencies before correction for series resistance) Curve 2 membrane conductance ((— X —) measured conductances without correction for series resistance).

Fig. 8. (A) Measured forces between two charged mica surfaces in 10" M KCl, where beyond 30 A (and out to 500 A) the repulsion is well described by conventional electrostatic double-layer force theory. Below 30 A there is an additional hydration repulsion, with oscillations superimposed below 15 A. (B) Forces between two uncharged lecithin bilayers in the fluid state in water. At long range there is an attractive van der Waals force, and at short range (i.e., below 25 A) there is a monotonically repulsive steric hydration force. (C) Forces between two hydrophobized mica surfaces in water where the hydrophobic interaction is much stronger than could be expected from van der Waals forces alone. From Israelachvili and Marra (1986).

Sun WJ, Tristram-Nagle S, Suter RM, Nagle JF. Stmcture of the ripple phase in lecithin bilayers. Proc. Natl. Acad. Sci. U.S.A. 1996 93 7008-7012. 

Phospholipid bilayers, liposomes and detergent micelles have often been used as model systems for membranes and have also proved convenient for ESR experiments. Lecithin bilayers, when prepared as films on a glass slide, are known to be formed in such a way that the lecithin molecules have their long axis perpendicular to the membrane surface. When the stearic acid derivatives (C) were incorporated into lecithin bilayers, it was found that they gave ESR spectra characteristic of... 

Here h is the total bilayer thickness (=4nm), is the dielectric thickness (=2.8nm for lecithin bilayers [93, 94]), and Em is the membrane permittivity (=2eo, where Eq is the vacuum permittivity). For vesicles with some initial tension Ob, the total tension reached during the pulse is simply... 

Bisseret, P, Wolff, G., Albrecht, A.-M. et al. (1983). A direct study of the cohesion of lecithin bilayers the effect of hopanoids and dihydroxycarotenoids. Biochemical and Biophysical Research Communications, 110, 320-4. 

LeNeveu, D. M., Rand, R. P Gingell, D. Parsegian, V. A. (1976a). Apparent modification of forces between lecithin bilayers. Science 191, 399—400. 

The stability of bilayers in the presence of polyene antibiotics has been investigated [199]. Pure lecithin bilayers were found to be stable in the presence of 40 /xM filipin or nystatin in contrast, bilayers consisting of equal parts cholesterol and lecithin were disrupted rapidly by filipin but considerably more slowly by nystatin. Bilayers consisting exclusively of cholesterol or bilayers with phospholipid sterol ratios of 10 1 were stable in the presence of filipin. When added to a sterol-containing lecithin bilayer, filipin removed the sterol from the membrane by non-polar association, changing the fluidity of the lipid chains in the bilayer, and ultimately caused membrane breakdown [200],... 

The structure of nystatin (8) is closely related to that of amphotericin B (11) except that in the nystatin molecule the double bond system is interrupted by saturation of the bond separating the tetraene and diene chromophores. This would allow the bending of an otherwise rigid structure. A similar structure to that of the amphotericin B-sterol pores has been proposed for nystatin in sterol—lecithin bilayers [154,203,249]. The permeability characteristics of nystatin pores closely resembled amphotericin B pores and it was even possible to form mixed pores when nystatin was added to one side of the bilayer and amphotericin B to the other [209]. 

Porphyrin bolaamphiphiles have been shown to form platelets with a thickness of 8 A in bulk water. Well-defined monolayers have been obtained with bolaamphiphilic porphyrins with two positive charges on each edge. Charge repulsion obviously first prevents crystallization and second unlimited growth of the isolated sheets. Their surface area is a few [ixn. In aqueous solution lecithin bilayers of unlimited extension (myelin figures) are known to have erne s below 10" M and can thus be considered as noncovalent polymers. ... 

W. I. Calhoun and G. G. Shipley, Sphingomyelin-Lecithin Bilayers and Their Interaction with Cholesterol, Biochemistry 18, 1717-1722 (1979). 

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