Delta-5 desaturase and its use in making polyunsaturated fatty acids

Abstract

Isolated nucleic acid fragments and recombinant constructs comprising such fragments encoding delta-5 desaturase along with a method of making long chain polyunsaturated fatty acids (PUFAs) using this delta-5 desaturase in plants and oleaginous yeast are disclosed.

1 - 21 . (canceled) 
     
     
         22 . Oil or by-products obtained from a transgenic seed obtained from an oilseed plant produced by a method comprising:
 (a) transforming an oilseed plant cell with a recombinant DNA construct comprising an isolated polynucleotide comprising:
 (i) a nucleotide sequence encoding a polypeptide having delta-5 desaturase activity, wherein the polypeptide has at least 80% amino acid identity, based on the Clustal W method of alignment, when compared to an amino acid sequence as set forth in SEQ ID NO:2; 
 (ii) a nucleotide sequence encoding a polypeptide having delta-5 desaturase activity, wherein the nucleotide sequence has at least 80% sequence identity, based on the BLASTN method of alignment, when compared to a nucleotide sequence as set forth in SEQ ID NO:1 or SEQ ID NO:3; 
 (iii) a nucleotide sequence encoding a polypeptide having delta-5 desaturase activity, wherein the nucleotide sequence selectively hybridizes under stringent conditions to a nucleotide sequence as set forth in SEQ ID NO:1 or SEQ ID NO:3; or 
 (iv) a complement of the nucleotide sequence of (a), (b) or (c), wherein the complement and the nucleotide sequence consist of the same number of nucleotides and are 100% complementary, 
 operably linked to at least one regulatory sequence and at least one additional recombinant DNA construct comprising an isolated polynucleotide, operably linked to at least one regulatory sequence, encoding a polypeptide selected from the group consisting of a delta-4 desaturase, a delta-5 desaturase, a delta-6 desaturase, a delta-8 desaturase, a delta-12 desaturase, a delta-15 desaturase, a delta-17 desaturase a delta-9 desaturase a delta-9 elongase a C 14/16  elongase a C 16/18  elongase, a C 18/20  elongase and a C 20/22  elongase; 
   (b) regenerating an oilseed plant from the transformed cell of step (a); and   (c) selecting those seeds obtained from the plants of step (b) having an altered level of polyunsaturated fatty acids when compared to the level in seeds obtained from a nontransformed oilseed plant.   
     
     
         23 . The oil or by-products of  claim 22 , wherein the oilseed plant is selected from the group consisting of soybean, Brassica species, sunflower, maize, cotton, flax, and safflower. 
     
     
         24 . (canceled) 
     
     
         25 . Food or feed which incorporates the oil of  claim 22 . 
     
     
         26 . Food or feed which incorporates the oil of  claim 23 . 
     
     
         27 - 29 . (canceled) 
     
     
         30 . Food or feed comprising an ingredient derived from the processing of a transgenic seed obtained from an oilseed plant produced by a method comprising:
 (a) transforming an oilseed plant cell with a recombinant DNA construct comprising an isolated polynucleotide comprising:
 (i) a nucleotide sequence encoding a polypeptide having delta-5 desaturase activity, wherein the polypeptide has at least 80% amino acid identity, based on the Clustal W method of alignment, when compared to an amino acid sequence as set forth in SEQ ID NO:2; 
 (ii) a nucleotide sequence encoding a polypeptide having delta-5 desaturase activity, wherein the nucleotide sequence has at least 80% sequence identity, based on the BLASTN method of alignment, when compared to a nucleotide sequence as set forth in SEQ ID NO:1 or SEQ ID NO:3; 
 (iii) a nucleotide sequence encoding a polypeptide having delta-5 desaturase activity, wherein the nucleotide sequence selectively hybridizes under stringent conditions to a nucleotide sequence as set forth in SEQ ID NO:1 or SEQ ID NO:3; or 
 (iv) a complement of the nucleotide sequence of (a), (b) or (c), wherein the complement and the nucleotide sequence consist of the same number of nucleotides and are 100% complementary, 
 operably linked to at least one regulatory sequence and at least one additional recombinant DNA construct comprising an isolated polynucleotide, operably linked to at least one regulatory sequence, encoding a polypeptide selected from the group consisting of a delta-4 desaturase, a delta-5 desaturase, a delta-6 desaturase, a delta-8 desaturase, a delta-12 desaturase, a delta-15 desaturase, a delta-17 desaturase, a delta-9 desaturase, a delta-9 elongase, a C 14/16  elongase, a C 16/18  elongase, a C 18/20  elongase and a C 20/22  elongase; 
   (b) regenerating an oilseed plant from the transformed cell of step (a); and   (c) selecting those seeds obtained from the plants of step (b) having an altered level of polyunsaturated fatty acids when compared to the level in seeds obtained from a nontransformed oilseed plant.   
     
     
         31 . The food or feed of  claim 30 , wherein the oilseed plant is selected from the group consisting of soybean,  Brassica  species, sunflower, maize, cotton, flax, and safflower. 
     
     
         32 . The oil or by-products of  claim 22  wherein the by-product is lecithin. 
     
     
         33 . The oil or by-products of  claim 23  wherein the by-product is lecithin. 
     
     
         34 - 36 . (canceled) 
     
     
         37 . The oil or by-products of  claim 22 , wherein the nucleotide sequence comprises SEQ ID NO:1 or SEQ ID NO:3. 
     
     
         38 . The oil or by-products of  claim 22 , wherein the amino acid sequence of the polypeptide comprises
 (a) SEQ ID NO:2; or   (b) an amino acid sequence that differs from the amino acid sequences in (a) by at least one conservative amino acid substitution.   
     
     
         39 . The oil or by-products of  claim 30 , wherein the nucleotide sequence comprises SEQ ID NO:1 or SEQ ID NO:3. 
     
     
         40 . The oil or by-products of  claim 30 , wherein the amino acid sequence of the polypeptide comprises
 (a) SEQ ID NO:2; or   (b) an amino acid sequence that differs from the amino acid sequences in (a) by at least one conservative amino acid substitution.