| abstract |
The present invention relates to a process for producing polyunsaturated fatty acids in an organism by introducing into the organism nucleic acids encoding Δ5-elongase activity polypeptides. Advantageously, these nucleic acid sequences may optionally be expressed in the organism together with other nucleic acid sequences encoding polypeptides of biosynthesis of the fatty acid or lipid metabolism. Nucleic acid sequences which code for Δ6-desaturase, Δ5-desaturase, Δ4-desaturase and / or Δ6-elongase activity are particularly advantageous. These desaturases and elongases are advantageously derived from Thalassiosira, Euglena or Ostreococcus. Furthermore, the invention relates to a process for the preparation of oils and / or triacylglycerides having an increased content of long-chain polyunsaturated fatty acids.n n n The present invention also relates, in a preferred embodiment, to a process for the preparation of unsaturated ω-3 fatty acids and to a process for the preparation of triglycerides having an increased content of unsaturated fatty acids, especially of ω-3 fatty acids having more than three double bonds. The invention relates to the production of a transgenic organism preferably a transgenic plant or a transgenic microorganism with increased content of unsaturated ω-3 fatty acids, oils or lipids with ω-3 double bonds due to the expression of the elongases and desaturases used in the process according to the invention advantageously in combination with ω-3-desaturases, for example an ω-3-desaturase from fungi of the family Pythiaceae such as the genus Phytophtora for example the genus and species Phytophtora infestans or an ω-3-desaturase from algae such as the family Prasinophyceae e.g. the genus Ostreococcus especially the genus and species Ostreococcus tauri or diatoms such as the genus Thalassiosira especially the genus and species Thalassiosira pseudonana.n n n The invention further relates to the nucleic acid sequences, nucleic acid constructs, vectors and organisms containing the nucleic acid sequences according to the invention, vectors containing the nucleic acid sequences and / or the nucleic acid constructs and transgenic organisms contain the aforementioned nucleic acid sequences, nucleic acid constructs and / or vectors.n n n Another part of the invention relates to oils, lipids and / or fatty acids prepared by the process according to the invention and their use. Moreover, the invention relates to unsaturated fatty acids and triglycerides having an increased content of unsaturated fatty acids and their use. |