Diacylglycerol acyltransferases for alteration of polyunsaturated fatty acids and oil content in oleaginous organisms

• US 7,273,746 B2
• Filed: 12/29/2004
• Issued: 09/25/2007
• Est. Priority Date: 11/04/2004
• Status: Expired due to Fees

• Current Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: Xue, Zhixiong, Yadav, Narendra S., Zhang, Hongxiang
• Primary Examiner(s): Prouty; Rebecca E.
• Assistant Examiner(s): Chowdhury; Iqbal
• Application Number:
  US11/024,544
• Publication Number:
  US 20060094086A1
• Time in Patent Office: 1,000 Days
• Field of Search: 435/193, 435/69.1, 435/254.11, 435/134, 536/23.3
• US Class Current: 435/254.2
• CPC Class Codes: C12N 9/1029 transferring groups other than amino-acyl groups (2.3.1)
• CPC Class Codes: C12P 7/6463 obtained from glyceride producing microorganisms, e.g. single cell oil
• CPC Class Codes: C12P 7/6472 containing polyunsaturated fatty acid [PUFA] residues, i.e. having two or more double bonds in their backbone

Abstract

Acyltransferases are provided, suitable for use in the manufacture of microbial oils enriched in omega fatty acids in oleaginous yeast (e.g., Yarrowia lipolytica). Specifically, genes encoding diacylglycerol acyltransferase (DGAT1) have been isolated from Y. lipolytica and Mortierella alpina. These genes encode enzymes that participate in the terminal step in oil biosynthesis in yeast. Each is expected to play a key role in altering the quantity of polyunsaturated fatty acids produced in oils of oleaginous yeasts.

Claims

1. An isolated nucleic acid molecule encoding a diacylglycerol acyltransferase-1 enzyme, selected from the group consisting of:

(a) an isolated nucleic acid molecule encoding the amino acid sequence as set forth in SEQ ID NO;

18; and

(b) an isolated nucleic acid molecule that hybridizes with (a) under the following hybridization conditions;

0.1×

SSC, 0.1% SDS, 65°

C. and washed with 2×

SSC, 0.1% SDS followed by 0.1×

SSC, 0.1% SDS; and

encodes a protein having diacylglycerol acyltransferase activity or an isolated nucleic acid molecule that is completely complementary to (a) or (b).

2. The isolated nucleic acid molecule of claim 1 as set forth in SEQ ID NO:

17.

3. A chimeric gene comprising the isolated nucleic acid molecule of claim 1 operably linked to suitable regulatory sequences.

4. An isolated transformed host cell comprising the chimeric gene of claim 3.

5. The transformed host cell of claim 4, selected from the group consisting of algae, bacteria, molds, fungi and yeasts.

6. The transformed host cell of claim 5, wherein the yeast is an oleaginous yeast.

7. The transformed host cell of claim 6, wherein the oleaginous yeast cell is selected from the group consisting of Yarrowia, Candida, Rhodotorula, Rhodosporidium, Cryptococcus, Trichosporon and Lipomyces.

8. The transformed host cell of claim 7, wherein the host cell is Yarrowia lipolytica.