Abstract
The major lipid class in photosynthetic tissues is formed by the galactolipids rich in linolenic acid. Great advances have been realized these last years towards the elucidation of the mechanism of the biosynthesis of polyunsaturated fatty acids. Linolenate is formed by two successive desaturations of oleate. On one side oleoyl-phosphatidylcholine (PC) is converted to linoleoyl-phosphatidylcholine in microsomes [1–4]. On the other side oleoyl-monogalactosyldiacylglycerol is desaturated in the chloroplast [5]. However the cellular site and the nature of the substrate for desaturation of linoleate to linolenate are still the matter of discussions. The microsomal fraction may be involved in the last desaturation : linoleoyl-PC could be desaturated to linolenoyl-PC and transferred subsquently to the chloroplast for galactolipid synthesis [6]. Another site of desaturation has been proposed : linoleate desaturation might occur in the chloroplast and the substrate of desaturation would be the monogalactosyldiacylglycerol (MGDG) [5]. The labelling studies with [1–14C] linoleate described in this paper support the view that desaturation of linoleate may involve diacylglycerols.
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© 1995 Springer Science+Business Media Dordrecht
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Ghouziel, KB., Paul, M. (1995). Are Diacylglycerols Possible Substrates for Linoleate Desaturation in Safflower Cotyledons (Carthamus tinctorius L.)?. In: Kader, JC., Mazliak, P. (eds) Plant Lipid Metabolism. Springer, Dordrecht. https://doi.org/10.1007/978-94-015-8394-7_10
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DOI: https://doi.org/10.1007/978-94-015-8394-7_10
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