Biosynthesis of C20 and C22 Fatty Acids by Developing Seeds of Limnanthes alba
- 1 October 1980
- journal article
- research article
- Published by Oxford University Press (OUP) in Plant Physiology
- Vol. 66 (4), 649-655
- https://doi.org/10.1104/pp.66.4.649
Abstract
The storage triacylglycerols of meadowfoam (L. alba) seeds are composed essentially of C20 and C22 fatty acids, which contain an unusual .DELTA.5 double bond. When [1-14C]acetate was incubated with developing seed slices, 14C-labeled fatty acids were synthesized with a distribution similar to the endogenous fatty acid profile. The major labeled product was cis-5-eicosenoate, with smaller amounts of palmitate, stearate, oleate, cis-5-octadecenoate, eicosanoate, cis-11-eicosenoate, docosanoate, cis-5-docosenoate, cis-13-docosenoate and cis-5,cis-13-docosadienoate. The label from [14C]acetate and [14C]malonate was used preferentially for the elongation of endogenous oleate to produce cis-[14C]11-eicosenoate, cis-13-[14C]docosenoate and cis-5,cis-13-[14C]docosadienoate and for the elongation of endogenous palmitate to produce the remaining C20 and C22 acyl species. The .DELTA.5 desaturation of the performed acyl chain and chain elongation of oleate and palmitate were demonstrated in vivo by incubation of the appropriate 1-14C-labeled free fatty acids. Using [1-14C]acyl-CoA thioesters as substrates, these enzyme activities were also demonstrated in vitro with a cell-free homogenate.Keywords
This publication has 14 references indexed in Scilit:
- Long Chain (C20 and C22) Fatty Acid Biosynthesis in Developing Seeds of Tropaeolum majusPlant Physiology, 1980
- Lipid extraction of tissues with a low-toxicity solventAnalytical Biochemistry, 1978
- The Biosynthesis of Linoleate from Oleoyl‐CoA via Oleoyl‐Phosphatidylcholine in Microsomes of Developing Safflower SeedsEuropean Journal of Biochemistry, 1978
- Labelling of glycerolipids in the cotyledons of developing oilseeds by [1-14C]acetate and [2-3H]glycerolBiochemical Journal, 1978
- Studies on Seed‐Oil Triglycerides Factors Controlling the Biosynthesis of Fatty Acids and Acyl Lipids in Subcellular Organelles of Maturing Crambe abyssinica SeedsEuropean Journal of Biochemistry, 1974
- Fat metabolism in higher plantsArchives of Biochemistry and Biophysics, 1974
- Conversion of lipids to fatty alcohols and lysolipids by NaBH4Chemistry and Physics of Lipids, 1973
- The biosynthesis of unsaturated fatty acids by bacilli. V. In vivo substrate specificities of fatty acid desaturases.1973
- Fat metabolism in higher plants. XLVI. Nature of the substrate and the product of oleyl coenzyme A desaturase from Carthamus tinctorius.1971
- Synthesis of linoleic acid by particulate system from safflower seedsBiochimica et Biophysica Acta (BBA) - Specialized Section on Lipids and Related Subjects, 1964