Abstract
Pigment leakage from sheep and horse erythrocytes and from red beet tissue induced by non-polar solvents was determined as a function of pH. The results were compared to disruption of multilamellar vesicles (MLV) composed of phospholipids with equimolar cholesterol under identical conditions of solvent exposure and pH. Solvent access to cholesterol was used to measure vesicle disruption. MLV were made from 1,2-dioleoyl phosphatidylethanolamine sphingomyelin (SP) and various phosphatidylcholines to simulate the major lipid components of membranes. Pigment leakage from erythrocytes caused by petroleum hydrocarbon (b.p. 60–80°C) was maximal at pH 2–4 and at pH 10, but minimal at pH 6.8; alcohols caused less pigment leakage than petroleum hydrocarbon. Betacyanin leakage from beet tissue induced by petroleum hydrocarbon was maximal at pH 2, with very little leakage at pH 4, 6.6 and pH 10. Alcohols caused minimal damage to beet tissue above pH 2. Cholesterol removal by petroleum hydrocarbon from MLV of mixed lipid composition was maximal at pH 2–4, reduced at pH 6.8 and minimal at pH 10. Lipid mixtures in which fatty acyl side chains of one phospholipid were of a different length than the other lost more sterol than mixtures in which the acyl side chains were of identical chain length. MLV with more than 25% SP lost more sterol than those with less or no SP. Results show that in mixtures of phospholipids, SP exposes the hydrocarbon phase of a bilayer to solvent extraction, a property that was also observed in native membranes. Erythrocyte membranes, which contain SP, were more severely damaged by petroleum hydrocarbon than beet cells, which have none. Membranes from erythrocytes were more prone to solvent disruption at pH 10 than MLV, but they were more resistant at physiological pH. It is suggested that conformational changes in membrane proteins due to shifts in pH cause exposure of hydrophobic portions of surrounding lipids to the environment. At neutral pH, the native conformation of proteins is expected to stabilize the bilayer of membranes.
Similar content being viewed by others
Abbreviations
- CAPS:
-
cyclohexylaminopropanesulfonic acid
- C/M:
-
chloroform/methanol 2∶1 (vol/vol)
- DOPC:
-
1,2-dioleoyl-sn-glycero-3-phosphocholine
- DOPE:
-
1,2-dioleoyl-sn-glycero-3-phosphoethanolamine
- DPPC:
-
1,2-dipalmitoyl-sn-glycero-3-phosphocholine
- HII :
-
reverse hexagonal phase
- MES:
-
2-(N-morpholino)ethanesulfonic acid
- MLV:
-
multilamellar vesicles
- PC:
-
phosphatidylcholine
- PE:
-
phosphatidylethanolamine
- PS:
-
phosphatidylserine
- SP:
-
sphingomyelin
- TLC:
-
thin-layer chromatography
References
Jacobsohn, M.K., Bazilian, L.S., Hardiman, J., and Jacobsohn, G.M. (1989)Lipids 24, 375–382.
Jacobsohn, M.K., Esfahani, M., and Jacobsohn, G.M. (1986)Lipids 21, 691–696.
deKruijff, B., Cullis, P.R., Verkleij, A.J., Hope, M.J., Van Echteld, C.J.A., and Taraschi, T.F. (1985)The Enzymes of Biological Membranes, Vol. 1 (Martonosi, A.N., ed.) 2nd edn., pp. 131–204, Plenum, New York.
Grunwald, C. (1968)Plant Physiol. 43, 484–488.
Beiss, U. (1969)Landwirtsch. Forsch. Sonderh. 23/1, 198–206.
Nelson, G.J. (1967)Biochim. Biophys. Acta 144, 221–232.
Lange, Y., D'Alessandro, J.S., and Small, D.M. (1979)Biochim. Biophys. Acta 556, 388–398.
Van Blitterswijk, W.J., Vander Meer, B.W., and Hilkmann, H. (1987)Biochemistry 26, 1746–1756.
Sankaram, M.B., and Thompson, T.E. (1990)Biochemistry 29, 10670–10675.
Schroeder, F., and Nemecz, G. (1989)Biochemistry 28, 5992–6000.
White, D.A. (1973)Form and Function of Phospholipids (Ansell, G.B., Dawson, R.M.C., and Hawthorne, J.N., eds.) 2nd edn., pp. 441–482, Elsevier, Amsterdam.
Hope, M.J., Redelmeier, T.E., Wong, K.F., Rodrigueza, W., and Cullis, P.R. (1989)Biochemistry 28, 4181–4187.
Kumar, A., and Gupta, C.M. (1984)Biochim. Biophys. Acta 769, 419–428.
Hope, M.J., and Cullis, P.R. (1987)J. Biol. Chem. 262, 4360–4366.
Liu, D., and Huang, L. (1989)Biochim. Biophys. Acta 981, 254–260.
Rand, R.P., Fuller, N.L., Gruner, S.M., and Parsegian V.A. (1990)Biochemistry 29, 76–87.
Liu, D., Zhou, F., and Huang, L. (1989)Biochem. Biophys. Res. Commun. 162, 326–333.
Hui, S.-W., and Sen, A. (1989)Proc. Natl. Acad. Sci. USA 86, 5825–5829.
Sunamoto, J., Goto, M., Iwamoto, K., Kondo, H., and Sato, T. (1990)Biochim. Biophys. Acta 1024, 209–219.
Yechiel, E., and Edidin, M. (1987)J. Cell. Biol. 105, 755–760.
Boggs, J.M., Wood, D.D., Moscarello, M.A., and Papahadjopoulos, D. (1977)Biochemistry 16, 2325–2329.
Author information
Authors and Affiliations
About this article
Cite this article
Jacobsohn, M.K., Lehman, M.M. & Jacobsohn, G.M. Cell membranes and multilamellar vesicles: Influence of pH on solvent induced damage. Lipids 27, 694–700 (1992). https://doi.org/10.1007/BF02536027
Received:
Revised:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02536027