Processes for producing polyunsaturated fatty acids in transgenic organisms

1. An isolated polynucleotide comprising a nucleic acid sequence selected from the group consisting of:

(a) the nucleic acid sequence of SEQ ID NO: 13;

(b) a nucleic acid sequence which codes for a polypeptide comprising the amino acid sequence of SEQ ID NO: 14;

(c) a nucleic acid sequence which codes for a polypeptide having at least 90% identity to a polypeptide which is encoded by the nucleic acid sequence of (a) or (b), where the polypeptide has Δ6-desaturase activity; and

(d) a nucleic acid sequence comprising a fragment of the nucleic acid of (a), (b) or (c), where the fragment codes for a polypeptide with Δ6-desaturase activity.

2. The polynucleotide of claim 1 , wherein the polynucleotide consists of RNA or DNA.

3. A vector comprising the polynucleotide of claim 1 .

4. The vector of claim 3 , wherein the vector is an expression vector.

5. The vector of claim 3 , wherein the vector comprises at least one further polynucleotide which encodes a further enzyme which is involved in the biosynthesis of lipids or fatty acids.

6. A host cell comprising the polynucleotide of claim 1 .

7. A host cell comprising the vector of claim 3 .

8. The host cell of claim 6 , wherein the host cell additionally comprises at least one further enzyme which is involved in the biosynthesis of lipids or fatty acids.

9. The vector of claim 5 , wherein the enzyme is 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), acyl-CoA:dysophospholipid 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 acetylenase(s), lipoxygenase(s), triacylglycerol lipase(s), allene oxide synthase(s), hydroperoxide lyase(s), fatty acid elongase(s), Δ4-desaturase(s), Δ5-desaturase(s), Δ6-desaturase(s), Δ8-desaturase(s), Δ9-desaturase(s), Δ12-desaturase(s), Δ5-elongase(s), Δ6-elongase(s), and Δ9-elongase(s).

10. The host cell of claim 8 , wherein the enzyme is 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), acyl-CoA:lysophospholipid 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 acetylenase(s), lipoxygenase(s), triacylglycerol lipase(s), allene oxide synthase(s), hydroperoxide lyase(s), fatty acid elongase(s), Δ4-desaturase(s), Δ5-desaturase(s), Δ6-desaturase(s), Δ8-desaturase(s), Δ9-desaturase(s), Δ12-desaturase(s), Δ5-elongase(s), Δ6-elongase(s), and Δ9-elongase(s).

11. A method of generating a polypeptide with Δ6-desaturase activity, comprising:

(a) expressing the polynucleotide of claim 1 in a host cell; and

(b) obtaining, from the host cell, the polypeptide which is encoded by the polynucleotide.

12. A polypeptide which is encoded by the polynucleotide of claim 1 .

13. A transgenic, nonhuman organism comprising the polynucleotide of claim 1 , wherein said organism is a plant or a microorganism.

14. A process for the production of a substance which has the structure shown in the general formula I hereinbelow

where the variables and substituents are as follows:

R 1 =hydroxyl, coenzyme A (thioester), lysophosphatidylcholine, lysophosphatidylethanolamine, lysophosphatidylglycerol, lysodiphosphatidylglycerol, lysophosphatidylserine, lysophosphatidylinositol, sphingo base or a radical of the formula II

R 2 =hydrogen, lysophosphatidylcholine, lysophosphatidylethanolamine, lysophosphatidylglycerol, lysodiphosphatidylglycerol, lysophosphatidylserine, lysophosphatidylinositol or saturated or unsaturated C 2 -C 24 -alkylcarbonyl,

R 3 =hydrogen, saturated or unsaturated C 2 -C 24 -alkylcarbonyl, or R 2 and R 3 independently of one another are a radical of the formula Ia:

n=2, 3, 4, 5, 6, 7 or 9, m=2, 3, 4, 5 or 6, and p=0 or 3;

the process comprising cultivating (i) a host cell comprising the polynucleotide of claim 1 or (ii) a transgenic, nonhuman organism comprising the polynucleotide of claim 1 under conditions which permit the biosynthesis of the substance.

15. The process of claim 14 for the production of an oil, lipid or fatty acid composition, further comprising formulating the substance as an oil, lipid or fatty acid composition.

16. The process of claim 15 , wherein the oil, lipid or fatty acid composition is formulated further to give a pharmaceutical product, a cosmetic product, a foodstuff, a feeding stuff, a fish food, or a food supplement.

17. The polynucleotide of claim 1 , wherein the polynucleotide comprises a nucleic acid sequence selected from the group consisting of:

(a) the nucleic acid sequence of SEQ ID NO: 13; and

(b) a nucleic acid sequence which codes for a polypeptide comprising the amino acid sequence of SEQ ID NO: 14.

18. The host cell of claim 6 , wherein the host cell is a plant cell.

19. A transgenic plant, plant cell, or plant part comprising the polynucleotide of claim 1 .

20. A transgenic microorganism comprising the polynucleotide of claim 1 .

21. An isolated polynucleotide comprising a nucleic acid sequence selected from the group consisting of:

(a) the nucleic acid sequence of SEQ ID NO: 13;

(b) a nucleic acid sequence which codes for a polypeptide comprising the amino acid sequence of SEQ ID NO: 14; and

(c) a nucleic acid sequence which codes for a polypeptide comprising an amino acid sequence having at least 90% sequence identity with the sequence of SEQ ID NO: 14, where the polypeptide has Δ6-desaturase activity.

22. A transgenic plant, plant cell, or plant part comprising the polynucleotide of claim 21 .

23. A transgenic plant, plant cell, or plant part comprising the polynucleotide of claim 17 .