Synthesis of long-chain polyunsaturated fatty acids by recombinant cell

Patent metadata

Field	Value
Publication number	US-9926579-B2
Application number	US-201715644647-A
Country	US
Kind code	B2
Filing date	Jul 7, 2017
Priority date	Apr 22, 2004
Publication date	Mar 27, 2018
Grant date	Mar 27, 2018

Abstract

The present invention relates to methods of synthesizing long-chain polyunsaturated fatty acids, especially eicosapentaenoic acid, docosapentaenoic acid and docosahexaenoic acid, in recombinant cells such as yeast or plant cells. Also provided are recombinant cells or plants which produce long-chain polyunsaturated fatty acids. Furthermore, the present invention relates to a group of new enzymes which possess desatorase or elongase activity that can be used in methods of synthesizing long-chain polyunsaturated fatty acids.

First claim

What is claimed is:

1. A Brassica plant cell for producing docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) in an esterified form as part of triacylglycerols in the plant cell, comprising
a polynucleotide which encodes a Δ5 elongase operably linked to a promoter which directs expression of the polynucleotide in the plant cell;
a polynucleotide which encodes a Δ4 desaturase whose amino acid sequence is at least 99.5% identical to the sequence set forth as SEQ ID NO:33, operably linked to a promoter which directs expression of the polynucleotide in the plant cell; and
an exogenous desaturase which desaturates an acyl-CoA substrate.

2. The Brassica plant cell of claim 1 which is a Brassica napus plant cell.

3. The Brassica napus plant cell of claim 2 which is a Brassica napus seed cell.

4. A Brassica napus seed comprising the Brassica napus seed cell of claim 3 .

5. A process for producing DPA and DHA in an esterified form as part of triacylglycerols comprising
i) obtaining the Brassica napus seed of claim 4 , and
ii) extracting triacylglycerols from the seed.

6. The process of claim 5 which further comprises purifying the extracted triacylglycerols.

7. A Brassica plant cell comprising
a polynucleotide which encodes a Δ5 elongase operably linked to a promoter which directs expression of the polynucleotide in the plant cell;
a polynucleotide which encodes a Δ6 elongase which has the amino acid sequence set forth as SEQ ID NO:31, operably linked to a promoter which directs expression of the polynucleotide in the plant cell;
a polynucleotide which encodes a Δ4 desaturase whose amino acid sequence is at least 99.5% identical to the sequence set forth as SEQ ID NO:33, operably linked to a promoter which directs expression of the polynucleotide in the plant cell;
a polynucleotide which encodes a Δ5 desaturase which has the amino acid sequence set forth as SEQ ID NO:18, operably linked to a promoter which directs expression of the polynucleotide in the plant cell;
a polynucleotide which encodes a Δ6 desaturase operably linked to a promoter which directs expression of the polynucleotide in the plant cell; and
an exogenous desaturase which desaturates an acyl-CoA substrate.

8. The Brassica plant cell of claim 7 , wherein the Δ6 desaturase is a Δ5/Δ6 bifunctional desaturase.

9. The Brassica plant cell of claim 7 which is a Brassica napus plant cell.

10. The Brassica napus plant cell of claim 9 which is a Brassica napus seed cell.

11. A Brassica napus seed comprising the Brassica napus seed cell of claim 10 .

12. The Brassica napus seed of claim 11 comprising docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) in an esterified form as part of triacylglycerols in the seed.

13. A process for producing DPA and DHA in an esterified form as part of triacylglycerols comprising
i) obtaining the Brassica napus seed of claim 12 , and
ii) extracting triacylglycerols from the seed.

14. The process of claim 13 which further comprises purifying the extracted triacylglycerols.

Assignees

• Commw Scient Ind Res Org

Inventors

• Singh Surinder Pal
• Robert Stanley Suresh
• Nichols Peter David
• Blackburn Susan Irene Ellis
• Zhou Xue-Rong
• Petrie James Robertson
• Green Allan Graham

Classifications

• A61P3/02

  Nutrients, e.g. vitamins, minerals · CPC title

• A61P3/00

  Drugs for disorders of the metabolism (of the blood or the extracellular fluid A61P7/00) · CPC title

• Y02P20/52

  using catalysts, e.g. selective catalysts · CPC title

• C11B1/10

  by extracting · CPC title

• C12N15/52

  Genes encoding for enzymes or proenzymes · CPC title