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. 1986 Feb;49(2):553–562. doi: 10.1016/S0006-3495(86)83665-7

Investigation of surface potential asymmetry in phospholipid vesicles by a spin label relaxation method.

S A Sundberg, W L Hubbell
PMCID: PMC1329495  PMID: 3006815

Abstract

In earlier work, Castle and Hubbell (1976) demonstrated the use of a spin-labeled amphiphile as a probe for the electrostatic potential at the outer surface of charged phospholipid vesicles. In recent experiments, we have shown that the hydrophobic anion tetraphenylboron (TPB) promotes transbilayer migration of the probe molecule. Relaxation data recorded following the rapid mixing of the probe with TPB-containing vesicle samples provides information about the electrostatic potentials at both the outer and inner vesicle surfaces. The measured potentials for both surfaces of asymmetrically screened vesicles were found to be in good agreement with theoretical values calculated using their known surface charge density. The method is also sensitive to transmembrane potentials as indicated by the response of the label to potentials created with the use of potassium concentration gradients and valinomycin.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. BARTLETT G. R. Phosphorus assay in column chromatography. J Biol Chem. 1959 Mar;234(3):466–468. [PubMed] [Google Scholar]
  2. Barton P. G. The influence of surface charge density of phosphatides on the binding of some cations. J Biol Chem. 1968 Jul 25;243(14):3884–3890. [PubMed] [Google Scholar]
  3. Cafiso D. S., Hubbell W. L. EPR determination of membrane potentials. Annu Rev Biophys Bioeng. 1981;10:217–244. doi: 10.1146/annurev.bb.10.060181.001245. [DOI] [PubMed] [Google Scholar]
  4. Cafiso D. S., Hubbell W. L. Estimation of transmembrane pH gradients from phase equilibria of spin-labeled amines. Biochemistry. 1978 Sep 5;17(18):3871–3877. doi: 10.1021/bi00611a030. [DOI] [PubMed] [Google Scholar]
  5. Cafiso D. S., Hubbell W. L. Estimation of transmembrane potentials from phase equilibria of hydrophobic paramagnetic ions. Biochemistry. 1978 Jan 10;17(1):187–195. doi: 10.1021/bi00594a028. [DOI] [PubMed] [Google Scholar]
  6. Cafiso D. S., Hubbell W. L. Transmembrane electrical currents of spin-labeled hydrophobic ions. Biophys J. 1982 Sep;39(3):263–272. doi: 10.1016/S0006-3495(82)84516-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Castle J. D., Hubbell W. L. Estimation of membrane surface potential and charge density from the phase equilibrium of a paramagnetic amphiphile. Biochemistry. 1976 Nov 2;15(22):4818–4831. doi: 10.1021/bi00667a011. [DOI] [PubMed] [Google Scholar]
  8. Chabre M., Cavaggioni A. Light induced changes in ionic flux in the retinal rod. Nat New Biol. 1973 Jul 25;244(134):118–120. doi: 10.1038/newbio244118a0. [DOI] [PubMed] [Google Scholar]
  9. Eisenberg M., Gresalfi T., Riccio T., McLaughlin S. Adsorption of monovalent cations to bilayer membranes containing negative phospholipids. Biochemistry. 1979 Nov 13;18(23):5213–5223. doi: 10.1021/bi00590a028. [DOI] [PubMed] [Google Scholar]
  10. Gaffney B. J., Mich R. J. Letter: A new measurement of surface charge in model and biological lipid membranes. J Am Chem Soc. 1976 May 12;98(10):3044–3045. doi: 10.1021/ja00426a076. [DOI] [PubMed] [Google Scholar]
  11. Huang C., Mason J. T. Geometric packing constraints in egg phosphatidylcholine vesicles. Proc Natl Acad Sci U S A. 1978 Jan;75(1):308–310. doi: 10.1073/pnas.75.1.308. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Hubbell W. L., Metcalfe J. C., Metcalfe S. M., McConnell H. M. The interaction of small molecules with spin-labelled erythrocyte membranes. Biochim Biophys Acta. 1970 Dec 1;219(2):415–427. doi: 10.1016/0005-2736(70)90219-1. [DOI] [PubMed] [Google Scholar]
  13. McLaughlin S., Mulrine N., Gresalfi T., Vaio G., McLaughlin A. Adsorption of divalent cations to bilayer membranes containing phosphatidylserine. J Gen Physiol. 1981 Apr;77(4):445–473. doi: 10.1085/jgp.77.4.445. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. SINGLETON W. S., GRAY M. S., BROWN M. L., WHITE J. L. CHROMATOGRAPHICALLY HOMOGENEOUS LECITHIN FROM EGG PHOSPHOLIPIDS. J Am Oil Chem Soc. 1965 Jan;42:53–56. doi: 10.1007/BF02558256. [DOI] [PubMed] [Google Scholar]
  15. Stark G. Negative hydrophobic ions as transport-mediators for positive ions: evidence for a carrier mechanism. Biochim Biophys Acta. 1980 Jul 16;600(1):233–237. doi: 10.1016/0005-2736(80)90428-9. [DOI] [PubMed] [Google Scholar]
  16. Waggoner A. S. Dye indicators of membrane potential. Annu Rev Biophys Bioeng. 1979;8:47–68. doi: 10.1146/annurev.bb.08.060179.000403. [DOI] [PubMed] [Google Scholar]

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