Phospholipids vesicles

Consider a phospholipid vesicle containing 10 mMNa ions. The vesicle is bathed in a solution that contains 52 mMNa ions, and the electrical potential difference across the vesicle membrane Ai/t = i/toutskie / inside = —30 mV. What is the electrochemical potential at 25°C for Na ions ... 

FIGURE 4.14 Effects of G-protein on the displacement of the muscarinic antagonist radioligand [sH]-L-quinuclidinyl benzylate by the agonist oxotremorine. Displacement in reconstituted phospholipid vesicles (devoid of G-protein sububits) shown in filled circles. Addition of G-protein (Go 5.9 nmol Py-subunit/3.4 nmol ao-IDP subunit) shifts the displacement curve to the left (higher affinity, see open circles) by a factor of 600. Data redrawn from [14]. 

Florio, V. A., and Stemweis, P. C. (1989). Mechanism of muscarinic receptor action on G0 in reconstituted phospholipid vesicles. J. Biol. Chem. 264 3909-3915. 

Phospholipid vesicles, uncoated or polyethylenglycol-coated. They can be used to vehicle dtugs, antibodies or nucleic acids to target cells. 

The increase in Ca is initiated rapidly and begins to recover after 1 min. The order of potency correlates fairly well with the solubilities of these compounds in organic solvents (37) and their abilities to accumulate in phospholipid vesicles (38), i.e., 6>y>a>p, but not with their insecticidal activity (y 6>a p 39). At these concentrations, crystals of p-, a-, and y-HCH were evident in the cell suspensions when we made simultaneous measurements of the right-angle light scatter, indicating that the order of aqueous solubilities is 6>y>a>p. However, stimulation by 6-HCH at concentrations below its aqueous solubility limit shows a typical dose dependency of the response (Figure 10). 

Aurora, T. S., Li, W., Cummins, H. Z., and Haines T. H. (1985). Prepai ation and characterization of monodisperse unilamellar phospholipid vesicles with selected diameters of from 300-600 nm, Biochim. Biophys. Acta. 820, 250-258. 

Barenholz, Y., Amselem, S., and Lichtenberg, D. (1979). A new method for preparation of phospholipid vesicles (liposomes). French press, FEES Lett.. 99, 210-214. 

Hauser, H., and Strauss, G. (1987). Stabilization of small unilamellar phospholipid vesicles during spray-drying, Biochim. 

Johnson, S. M. (1973). The effect of charge and cholesterol on the size and thickness of sonicated phospholipid vesicles, Biochim. Biophys. Acta, 307, 27-41. 

Mayhew, E., Papahadjopoulos, D., Rustum, Y. M., and Dave, C. (1976). Inhibition of tumor cell growth in vitro and in vivo by ARA-C entrapped within phospholipid vesicles. Cancer Res.. 36. 4406-4411. 

K., McKenna, R. J., Smith, J. D., Bouzaglou, S. A., Callahan, R. A., Baldeschwieler, J., and Crossley, R. J. (1988). Successful imaging of human cancer with indium-lll-labled phospholipid vesicles. Cancer. 62. 905-911. 

Ueno, M., Tanford, C., and Reynolds, J. A. (1984). Phospholipid vesicle formation using nonionic detergents with low monomer solubility. Kinetic factors determine vesicle size and polydis-persity. Biochemistry, 3070-3076. 

Hinton, DP Johnson, CS, Diffusion Coefficients, Electrophoretic Mobilities, and Morphologies of Charged Phospholipid Vesicles by Pulsed Field Gradient NMR and Electron Microscopy, Journal of Colloid and Interface Science 173, 364, 1995. 

Modeling Pardaxin Channel. The remarkable switching of conformation in the presence of detergents or phospholipid vesicles (5) suggests that pardaxin is a very flexible molecule. This property helps to explain the apparent ability of pardaxin to insert into phospholipid bilayers. In addition, it is consistent with the suggestion that the deoxycholate-like aminoglycosteroids (5,7) present in the natural secretion from which pardaxin is purified (5) serve to stabilize its dissociated conformation. The question of the mechanism by which pardaxin assembles within membranes is important for understanding pore formation and its cytolytic activity (5). 

Hope, M.J. et al.. Generation of mnltUamellar and nnilameUar phospholipid vesicles, Chem. Phys. Lipids, 40, 89, 1986. 

C. N. Partitioning of ionising molecules between aqueous buffers and phospholipid vesicles. J. Pharm. Sci. 1995, 84, 1180-1183. 

Wakamatsu, K., Takeda, A., Tachi, T., Matsuzaki, K. Dimer structure of magainin 2 bound to phospholipid vesicles. Biopolymers 2002, 64, 314—327. 

As an example of suspected endocrine disruptors (EDs), studies of the estrogenic action of bisphenol A (BPA) have been in progress in medical, physiological, and biological fields. In this situation, physicochemical approaches are required to get the structural information of BPA trapped in biomembranes. Most recently, we have determined the site and the orientation of BPA trapped in phospholipid vesicles by NMR, using the HCS rule [47]. In particular, we have succeeded in monitoring the NMR spectral changes of phospholipid vesicles, which are induced by the BPA delivery. 

Biegel, C. M. Gould, J. M., Kinetics of hydrogen ion diffusion across phospholipid vesicle membranes, Biochemistry 20, 3474-3479 (1981). 

A trianionic zinc porphyrin anchored to a membrane by an imidazole link has been used to bind cytochrome c at the membrane surface. UV spectra confirmed the insertion of the zinc porphyrin into the phospholipid vesicle and was used to study surface association of cytochrome c. 

Lazrak, T., A. Milon, G. Wolff, A.M. Albrecht, M. Miehe, G. Ourisson, and Y. Nakatani. 1987. Comparison of the effects of inserted C40- and C50-terminally dihydroxylated carotenoids on the mechanical properties of various phospholipid vesicles. Biochim. Biophys. Acta 903 132-141. 

Starke-Peterkovic T, Clarke RJ (2009) Effect of headgroup on the dipole potential of phospholipid vesicles. Eur Biophys J 39 103-110... 

Crawford AR, Smith AJ, Hatch VC, Oude Elferink RP, Borst P, Crawford JM. Hepatic secretion of phospholipid vesicles in the mouse critically depends on mdr2 or MDR3 P-glycoprotein expression. Visualization by electron microscopy. J Clin Invest 1997 100(10) 2562-2567. 

Enoch, H.C., and Strittmattcr, P. (1979) Formation and properties of 100-A-diamctcr, singlebilayer phospholipid vesicles. Proc. Natl. Acad. Sci. USA 76, 145-149. 

Huang, C. (1969) Studies of phospholipid vesicles. Formation and physical characteristics. Biochemistry 8, 344. 

Reeves, I.P., and Dowben, R.M. (1969) Formation and properties of thin-walled phospholipid vesicles. J. Cell Physiol. 73, 49. 

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