Method for producing arachidonic acid in transgenic organisms

• US 20050089879A1
• Filed: 01/30/2004
• Published: 04/28/2005
• Est. Priority Date: 07/31/2001
• Status: Abandoned Application

• Current Assignee: IPK Institut Fur Pflanzengenetik und Kulturpflanzenforschung
• Original Assignee: IPK Institut Fur Pflanzengenetik und Kulturpflanzenforschung
• Inventors: Feussner, Ivo, Kindl, Helmut, Hornung, Ellen, Korfei, Martina, Pernstich, Christian
• Application Number:
  US10/769,647
• Publication Number:
  US 20050089879A1
• Time in Patent Office: Days
• US Class Current: 435/6
• CPC Class Codes: C12N 15/8247 involving modified lipid metabolism, e.g. seed oil composition
• CPC Class Codes: C12N 9/0083 Miscellaneous (1.14.99)

Abstract

The invention relates to a method for the production of arachidonic acid in transgenic organisms, especially in transgenic plants and yeasts. The invention also relates to DNA sequences coding for a protein with enzymatic activity of a Δ5-desaturase from Phytophthera megasperma. The invention further relates to transgenic plants and plant cell and transgenic yeasts containing a nucleic acid molecule comprising a DNA sequence according to the present invention and having, on the basis thereof, an enhanced arachidonic acid synthesis in comparison with wild-type cells. The invention also relates to harvest products and propagating material of transgenic plants.

Claims

1. An isolated DNA sequence which codes for a protein having the enzymatic activity of a Δ

5-desaturase, wherein the enzymatic activity is specific solely for dihomo-γ

-linolenic acid.

2. The DNA sequence according to claim 1, wherein the sequence is selected from the group consisting of:

a) a DNA sequence comprising a nucleotide sequence that codes for the amino acid sequence identified in SEQ ID No. 2 or a fragment thereof,

b) a DNA sequence comprising the coding nucleotide sequence given in SEQ ID No. 1 or a fragment thereof,

c) a DNA sequence comprising a nucleotide sequence, or a fragment of said nucleotide sequence, that hybridizes to a complementary strand of the coding nucleotide sequence from a) or b),

d) a DNA sequence comprising a nucleotide sequence, or fragment of said nucleotide sequence, which is degenerate to a nucleotide sequence from c),

e) a DNA sequence representing a derivative, an analogue or a fragment of a coding nucleotide sequence from a), b), c) or d).

3. The DNA sequence according to claim 1, originating from Phytophthora megasperma.

4. The DNA sequence according to claim 2;

originating from Phytophthora megasperma.

5. A recombinant nucleic acid molecule, comprising:

a regulatory sequence of a promoter which is active in a target cell, preferably a plant cell or a yeast cell, operatively linked to a DNA sequence according to claim 1.

6. The recombinant nucleic acid molecule of claim 5, further comprising a regulatory sequence operatively linked thereto, which can serve as transcription, termination and/or polyadenylation signals in the target cell.

13. A transgenic plant cell or a transgenic yeast cell comprising a DNA sequence or a recombinant nucleic acid molecule according to claim 1.

14. A transgenic plant cell or a transgenic yeast cell comprising a DNA sequence or a recombinant nucleic acid molecule according to claim 2.

18. A transgenic plant or a plant part, comprising the nucleic acid molecule according to claim 1, wherein said transgenic plant or plant part is selected from the group consisting of:

a transgenic harvest product and a transgenic propagating material.

19. The transgenic plant or plant part of claim 18, wherein said transgenic propagating material is selected from the group consisting of:

a protoplast, a plant cell, calli, a seed, a tuber, a cutting, and the transgenic progeny of the transgenic plant.

20. A method for producing arachidonic acid in a transgenic plant, a plant cell, a yeast cell, or a cell culture, comprising:

a) transferring a nucleic acid molecule according to claim 1 to a plant, a plant cell, a yeast cell, or a cell culture,

b) producing arachidonic acid by expression of the nucleic acid molecule according to claim 1 in the transgenic cell, and

c) obtaining arachidonic acid from the transgenic plant, the plant cell, the yeast cell, or the cell culture.

21. The method of claim 20, wherein the producing arachidonic acid by expression of the nucleic acid molecule further comprises the addition of dihomo-γ

-linolenic acid.

7. A recombinant protein having the enzymatic activity of a Δ

5-desaturase, wherein the enzymatic activity is specific for dihomo-γ

-linolenic acid.

8. The recombinant protein according to claim 7, originating from Phytophthora megasperma.

9. A method for generating a plant cell or a yeast cell having an increased content of arachidonic acid compared to a wild-type plant or a wild-type cell, comprising:

a) producing a recombinant nucleic acid molecule comprising the following elements in 5′

→

3′

direction;

a regulatory sequence of a promoter which is active in a plant cell or a yeast cell,

a nucleic acid sequence, which codes for a protein having the enzymatic activity of a Δ

5-desaturase that is specific for dihomo-γ

-linolenic acid, operatively linked thereto; and

b) transferring the nucleic acid molecule from a) to a plant cell or a yeast cell.

10. The method of claim 9, wherein the nucleic acid molecule further comprises at least one operably linked regulatory sequence which can serve as transcription, termination, and/or polyadenylation signals.

11. The method of claim 9, further comprising obtaining at least one transformed plant cell or at least one transformed yeast cell.

12. The method of claim 9, further comprising regenerating a plant from the plant cell.

15. A transgenic plant cell or a transgenic yeast cells comprising a DNA sequence or a recombinant nucleic acid molecule produced by a method according to claim 9.

16. A transgenic plant comprising a plant cell produced according to the method of claim 9.

17. A transgenic plant produced according to the method of claim 12.