Ca2+ induced phase separations in phospholipid mixtures.

W Tamura-Lis; E J Reber; B A Cunningham; J M Collins; L J Lis

doi:10.1016/0009-3084(86)90105-2

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Ca2+ induced phase separations in phospholipid mixtures.

W Tamura-Lis·E J Reber·B A Cunningham·J M Collins·L J Lis

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Abstract

We have probed the character of the observed phase separation in mixtures of phosphatidylcholines (PC) and/or phosphatidylethanolamines (PE) in the presence of CaCl2 solutions. Egg yolk phosphatidylethanolamine (EYPE) and a 1:1 molar ratio of dioleoylphosphatidylcholine/dioleoylphosphatidylethanolamine (DOPC/DOPE) were observed to undergo phase separation in CaCl2 solutions, as was previously observed for egg yolk phosphatidylcholine (EYPC) (L.J. Lis et al. Biochemistry, 20 (1981) 1771-1777). However, the mixed chain lipid, palmitoyloleoyl-PC, yielded only a single phase in water or CaCl2 solution. We hypothesize that two lipid species are necessary for the observed phase separation to occur, but that the separation itself is not a function of the individual lipid species, but of the mixture.

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Calcium Cholesterol Kinetics Lipid Bilayers Models, Biological Phosphatidylcholines Structure-Activity Relationship X-Ray Diffraction Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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W Tamura-Lis, E J Reber, B A Cunningham, J M Collins, L J Lis. 1986. Ca2+ induced phase separations in phospholipid mixtures.. https://doi.org/10.1016/0009-3084(86)90105-2

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