Method for the Production of Polyunsaturated Fatty Acids

Abstract

The present invention relates to a process for producing polyunsaturated fatty acids in an organism by introducing nucleic acids into the organism which code for polypeptides having acyl-CoA:lysophospholipid a cyltransferase activity. Advantageously, these nucleic acid sequences may, if appropriate together with further nucleic acid sequences coding for biosynthesis polypeptides of the fatty acid or lipid metabolism, be expressed in the transgenic organism. The invention furthermore relates to the nucleic acid sequences, to nucleic acid constructs comprising the nucleic acid sequences of the invention, to vectors comprising the nucleic acid sequences and/or the nucleic acid constructs and to transgenic organisms comprising the abovementioned nucleic acid sequences, nucleic acid constructs and/or vectors. A further part of the invention relates to oils, lipids and/or fatty acids produced by the process of the invention and to their use.

1 . A transgenic plant or plant cell comprising a heterologous acyl-CoA:lysophospholipid-acyltransferase (LPLAT) gene, wherein said plant or plant cell has an increased content of polyunsaturated fatty acids in comparison with a corresponding non-transgenic plant or plant cell lacking said heterologous LPLAT gene. 
     
     
         2 . The transgenic plant or plant cell of  claim 1 , wherein said heterologous LPLAT gene is integrated into the genome of said plant or plant cell and replaces a LPLAT gene native to said plant or plant cell by recombination. 
     
     
         3 . The transgenic plant or plant cell of  claim 1 , wherein the polyunsaturated fatty acids produced in said plant or plant cell comprises C 18 -, C 20 - and/or C 22 -fatty acids with at least two double bonds. 
     
     
         4 . The transgenic plant or plant cell of  claim 1 , further comprises at least one heterologous nucleic acid encoding an enzyme of the fatty acid or lipid metabolism. 
     
     
         5 . The transgenic plant or plant cell of  claim 4 , wherein the at least one heterologous nucleic acid encodes an enzyme of the fatty acid or lipid metabolism selected from the group consisting of acyl-CoA dehydrogenase(s), acyl-ACP [=acyl carrier protein] desaturase(s), acyl-ACP thioesterase(s), fatty acid acyltransferase(s), fatty acid synthase(s), fatty acid hydroxylase(s), acetyl-coenzyme A carboxylase(s), acyl-coenzyme A oxidase(s), fatty acid desaturase(s), fatty acid acetylenases, lipoxygenases, triacylglycerol lipases, allenoxide synthases, hydroperoxide lyases and fatty acid elongase(s). 
     
     
         6 . The transgenic plant or plant cell of  claim 4 , wherein the at least one heterologous nucleic acid encodes an enzyme of the fatty acid or lipid metabolism selected from the group consisting of Δ4-desaturases, Δ5-desaturases, Δ6-desaturases, Δ8-desaturases, Δ9-desaturases, Δ12-desaturases, Δ5-elongases, Δ6-elongases and Δ9-elongases. 
     
     
         7 . The transgenic plant or plant cell of  claim 5 , wherein the plant is an oil crop plant, or wherein the plant cell is an oil crop plant cell. 
     
     
         8 . A method for modulating production of polyunsaturated fatty acids in a non-human organism, comprising:
 (a) obtaining a non-human organism comprising a heterologous LPLAT gene; and   (b) growing said non-human organism under conditions so that said heterologous LPLAT gene is expressed,   wherein expression of said heterologous LPLAT gene modifies production of polyunsaturated fatty acids in said non-human organism.   
     
     
         9 . The method of  claim 8 , wherein said heterologous LPLAT gene is integrated into the genome of said non-human organism and replaces a LPLAT gene native to said non-human organism by recombination. 
     
     
         10 . The method of  claim 8 , wherein the polyunsaturated fatty acids produced in said non-human organism comprises C 18 -, C 20 - and/or C 22 -fatty acids with at least two double bonds. 
     
     
         11 . The method of  claim 8 , wherein the non-human organism further comprises at least one heterologous nucleic acid encoding an enzyme of the fatty acid or lipid metabolism. 
     
     
         12 . The method of  claim 11 , wherein the at least one heterologous nucleic acid encodes an enzyme of the fatty acid or lipid metabolism selected from the group consisting of acyl-CoA dehydrogenase(s), acyl-ACP [=acyl carrier protein] desaturase(s), acyl-ACP thioesterase(s), fatty acid acyltransferase(s), fatty acid synthase(s), fatty acid hydroxylase(s), acetyl-coenzyme A carboxylase(s), acyl-coenzyme A oxidase(s), fatty acid desaturase(s), fatty acid acetylenases, lipoxygenases, triacylglycerol lipases, allenoxide synthases, hydroperoxide lyases and fatty acid elongase(s). 
     
     
         13 . The method of  claim 11 , wherein the at least one heterologous nucleic acid encodes an enzyme of the fatty acid or lipid metabolism selected from the group consisting of Δ4-desaturases, Δ5-desaturases, Δ6-desaturases, Δ8-desaturases, Δ9-desaturases, Δ12-desaturases, Δ5-elongases, Δ6-elongases and Δ9-elongases. 
     
     
         14 . The method of  claim 8 , wherein the non-human organism is an oil crop plant. 
     
     
         15 . A transgenic plant or plant cell capable of producing docosahexaenoic acid (DHA), wherein said plant or plant cell comprises a heterologous LPLAT gene, and wherein expression of said heterologous LPLAT gene leads to the production of DHA in said plant or plant cell. 
     
     
         16 . The transgenic plant or plant cell of  claim 15 , wherein said heterologous LPLAT gene is integrated into the genome of said plant or plant cell and replaces a LPLAT gene native to said plant or plant cell by recombination. 
     
     
         17 . The transgenic plant or plant cell of  claim 15 , further comprises at least one heterologous nucleic acid encoding an enzyme of the fatty acid or lipid metabolism. 
     
     
         18 . The transgenic plant or plant cell of  claim 17 , wherein the at least one heterologous nucleic acid encodes an enzyme of the fatty acid or lipid metabolism selected from the group consisting of acyl-CoA dehydrogenase(s), acyl-ACP [=acyl carrier protein] desaturase(s), acyl-ACP thioesterase(s), fatty acid acyltransferase(s), fatty acid synthase(s), fatty acid hydroxylase(s), acetyl-coenzyme A carboxylase(s), acyl-coenzyme A oxidase(s), fatty acid desaturase(s), fatty acid acetylenases, lipoxygenases, triacylglycerol lipases, allenoxide synthases, hydroperoxide lyases and fatty acid elongase(s). 
     
     
         19 . The transgenic plant or plant cell of  claim 17 , wherein the at least one heterologous nucleic acid encodes an enzyme of the fatty acid or lipid metabolism selected from the group consisting of Δ4-desaturases, Δ5-desaturases, Δ6-desaturases, Δ8-desaturases, Δ9-desaturases, Δ12-desaturases, Δ5-elongases, Δ6-elongases and Δ9-elongases. 
     
     
         20 . The transgenic plant or plant cell of  claim 15 , wherein the plant is an oil crop plant, or wherein the plant cell is an oil crop plant cell.