Production of polyunsaturated fatty acids by expression of polyketide-like synthesis genes in plants

• US 6,140,486 A
• Filed: 06/04/1998
• Issued: 10/31/2000
• Est. Priority Date: 06/04/1997
• Status: Expired due to Term

• Current Assignee: Monsanto Company (Bayer AG)
• Original Assignee: Calgene Incorporated (Pharmacia Corp.)
• Inventors: Lassner, Michael, Facciotti, Daniel, Metz, James George
• Primary Examiner(s): McElwain, Elizabeth F.
• Application Number:
  US09/090,793
• Time in Patent Office: 880 Days
• Field of Search: 536/23.2, 435/69.1
• US Class Current: 536/23.2
• CPC Class Codes: C07K 14/21 from Pseudomonadaceae (F)
• CPC Class Codes: C07K 14/28 from Vibrionaceae (F)
• CPC Class Codes: C12N 15/52 Genes encoding for enzymes or proenzymes
• CPC Class Codes: C12N 15/8247 involving modified lipid metabolism, e.g. seed oil composition
• CPC Class Codes: C12P 7/6427 Polyunsaturated fatty acids [PUFA], i.e. having two or more double bonds in their backbone
• CPC Class Codes: C12P 7/6434 Docosahexenoic acids [DHA]
• CPC Class Codes: C12P 7/6472 containing polyunsaturated fatty acid [PUFA] residues, i.e. having two or more double bonds in their backbone

Abstract

The present invention relates to compositions and methods for preparing poly-unsaturated long chain fatty acids in plants, plant parts and plant cells, such as leaves, roots, fruits and seeds. Nucleic acid sequences and constructs encoding PKS-like genes required for the poly-unsaturated long chain fatty acid production, including the genes responsible for eicosapentenoic acid production of Shewanella putrefaciens and novel genes associated with the production of docosahexenoic acid in Vibrio marinus are used to generate transgenic plants, plant parts and cells which contain and express one or more transgenes encoding one or more of the PKS-like genes associated with such long chain polyunsaturated fatty acid production. Expression of the PKS-like genes in the plant system permits the large scale production of poly-unsaturated long chain fatty acids such as eicosapentenoic acid and docosahexenoic acid for modification of the fatty acid profile of plants, plant parts and tissues. Manipulation of the fatty acid profiles allows for the production of commercial quantities of novel plant oils and products.

Claims

1. An isolated nucleic acid comprising:

a Vibrio marinus nucleotide sequence selected from the group consisting of the ORF 6, ORF 7, ORF 8 and ORF 9, wherein the start and last codons for ORF 6 are 411 and 8269, for ORF 7 are 8526 and 11177, for ORF 8 are 11226 and 17282 and for ORF 9 are 17471 and 19135 as encoded by SEQ ID NO;

13 and as shown in FIG. 6.

2. An isolated nucleic acid comprising:

a nucleotide sequence which encodes a polypeptide of a polyketide-like synthesis system, wherein said system produces a docosahexanoic acid when expressed in a host cell, and

wherein said nucleotide sequence is a Vibrio marinus ORF 8, wherein the start and last codons for ORF 8 are 11226 and 17282 as encoded by SEQ ID NO;

13 and as shown in FIG. 6.

3. An isolated nucleic acid comprising:

a nucleotide sequence which is substantially identical to a sequence of at least 50 nucleotides of a Vibrio marinus nucleotide sequence selected from the group consisting of ORF 6, ORF 7, ORF 8 and ORF 9, wherein the start and last codons for ORF 6 are 411 and 8269, for ORF 7 are 8526 and 11177, for ORF 8 are 11226 and 17282 and for ORF 9 are 17471 and 19135 as encoded by SEQ ID NO;

13 and as shown in FIG. 6.