Conjugated linoleic acid isomerase and a process for the production of conjugated linoleic acid

1. An isolated nucleic acid molecule which encodes a polypeptide with conjugated linoleic acid isomerase activity, or the full complement thereof, selected from the group consisting of:

a) a nucleic acid molecule comprising the nucleotide sequence set forth in SEQ ID NO: 1,

b) a nucleic acid molecule comprising a nucleotide sequence which encodes a polypeptide sequence comprising the amino acid sequence as set forth in SEQ ID NO:2,

c) a nucleic acid molecule comprising a nucleotide sequence which is a derivative of the nucleic acid sequence shown in SEQ ID NO: 1, which encodes a polypeptide having at least 98% identity to the entire amino acid sequence as set forth in SEQ ID NO:2 without substantially reducing the enzymatic activity of the polypeptide; and

d) a nucleic acid molecule comprising a nucleotide sequence which is at least 95% identical to the entire nucleotide sequence set forth in SEQ ID NO:1 and encodes a polypeptide having conjugated linoleic acid isomerase activity.

2. A nucleic acid construct comprising a nucleic acid molecule of claim 1 , where the nucleic acid molecule is linked to one or more regulatory signals.

3. A vector comprising a nucleic acid molecule of claim 1 or the nucleic acid construct of claim 2 .

4. A transgenic microorganism comprising at least one nucleic acid molecule of claim 1 or at least one nucleic acid construct of claim 2 .

5. The transgenic microorganism of claim 4 , which is a bacterium.

6. A process for the production of conjugated linoleic acid comprising cultivating a recombinant microorganism into which the nucleic acid molecule of claim 1 or the nucleic acid construct of claim 4 has been introduced in the presence of linoleic acid and isolating the formed conjugated linoleic acid.

7. The process of claim 6 wherein the conjugated linoleic acid is cis-9, trans-11 octadecadienoic acid.

8. The process of claim 6 wherein the microorganism is selected from the group consisting of Bifidobacterium breve, Bifidobacterium dentium and Bifidobacterium pseudocatenulatum.

9. The process of claim 6 wherein the concentration of conjugated linoleic acid in the culture medium is higher than 1 mg/ml.

10. A process for the production of conjugated linoleic acid which comprises introducing at least one nucleic acid sequence as claimed in claim 1 or at least one nucleic acid construct as claimed in claim 2 into an oil-producing organism, growing this organism, isolating the oil contained in the organism and liberating the fatty acids contained in the oil.

11. A process for the production of triglycerides with an increased content of conjugated linoleic acid, which comprises introducing at least one nucleic acid sequence as claimed in claim 1 or at least one nucleic acid construct as claimed in claim 4 into an oil-producing organism, growing this organism and isolating the oil contained in the organism.

12. The process of claim 10 , wherein the organism is a microorganism.

13. The process of claim 10 , wherein the organism is a microorganism of the genera Bifidobacterium, Propionibacterium, Lactobacillus or Butyrivibrio.

14. The process of claim 10 , wherein the organism is a microorganism of the genus Bifidobacterium.

15. The process of claim 6 , wherein the microorganism is of the genus Bifidobacterium.

16. The process of claim 7 wherein the microorganism is selected from the group consisting of Bifidobacterium breve, Bifidobacterium dentium and Bifidobacterium pseudocatenulatum.

17. The process of claim 7 wherein the concentration of conjugated linoleic acid in the culture medium is higher than 1 mg/ml.