Lipid composition of the plasma-membrane of the halotolerant alga, Dunaliella salina - Sheffer, M.; Fried, A.; Gottlieb, H.E.; Tietz, A.; Avron, M. (Elsevier)
The major lipids of the isolated plasma-membrane of the halotolerant alga Dunaliella salina are diacylglyceroltrimethylhomoserine (DGTS, 23.5%), sterol peroxides (7-dehydroporiferasterol peroxide and ergosterol peroxide, 22%), phosphatidylcholine (13%) and phosphatidylethanolamine (11%). Free sterols comprised 5% of the lipids and contained predominantly 7-dehydroporiferasterol and ergosterol. The major fatty acids of the plasma-membrane were palmitic (31%), oleic (13%), linoleic (20%) and γ-linolenic (17%) acids. In constrast to the whole cells, the plasma-membrane contained less (11%) α-linolenic acid and no 16-carbon unsaturated fatty acids. Sterol peroxides were identified by ^1H-NMR and ^1^3C-NMR spectroscopy, mass spectrometry, and by comparison on thin-layer chromatography to the product of ergosterol photooxygenation. We believe that this is the first report on the occurrence of sterol peroxides as major constituents of a biological membrane. It is suggested that they may play a role in the unusual membrane-permeability properties of the plasma-membrane of Dunaliella.
http://linkinghub.elsevier.com/retrieve/pii/0005-2736(86)90344-5
Keywords: W; V; WW-YZ; U