Methods and compositions for producing squalene using yeast
Provided herein compositions and methods for producing isoprenoids, including squalene. In certain aspects and embodiments provided are genetically converted yeast and uses therefore. In some aspects and embodiments, the genetically converted yeast produce isoprenoids, preferably squalene. Also are provided methods of producing squalene using a genetically converted yeast or a non-genetically converted yeast. The invention also provides squalene produced by genetically converted yeast or non-genetically converted yeast.
1. A method of producing squalene by a yeast, said method comprising cultivating said yeast with an antifungal agent; wherein the yeast is a Yarrowia lipolytica strain selected from the group consisting of ATCC 20688, ATCC 90811, ATCC 90904, ATCC 90812, ATCC MYA-2613, or Yeastern polg, wherein the antifungal agent is an allylamine antifungal agent, and wherein the yeast expresses an exogenous squalene synthase gene, thereby genetically altering the yeast.
2. The method of claim 1 , wherein the yeast is a genetically converted yeast and wherein the method comprises increasing or decreasing activity or expression of one or more enzymes in the isoprenoid biosynthesis pathway, wherein said enzyme activity or expression is increased or decreased by one or more designed mutations, wherein said one or more designed mutations are at defined positions within said enzyme, wherein said genetically converted yeast produces increased quantities of isoprenoid as compared to the native yeast.
3. The method of claim 1 , wherein the antifungal agent is an allylamine antifungal agent at a concentration between 10 to 15 μg/ml.
4. The method of claim 2 , wherein said one or more enzymes are mutated with gene repair oligonucleobases.
5. The method of claim 4 , wherein said gene repair oligonucleobase is selected from the group consisting of mixed duplex oligonucleotides, non-nucleotide containing molecules, and single stranded oligodeoxynucleotides.
6. The method of claim 5 , wherein said gene repair oligonucleobase is a mixed duplex oligonucleotide.
7. The method of claim 6 , wherein said mixed duplex oligonucleotide is fewer than 100 nucleotides but more than 50 nucleotides.
8. The method according claim 5 , wherein the first and second strands of the mixed duplex oligonucleotide contain two regions that are homologous with two fragments of the target gene.
9. The method according to claim 2 , wherein said one or more enzymes include an enzyme selected from the group consisting of acetyl-CoA carboxylase (“ACCase”), HMG-CoA reductase, squalene epoxidase, squalene synthase, ATP citrate lyase, ATP citrate synthase, mevalonate kinase, glycerol kinase and 5-aminolevulinate synthase.
10. The method according to claim 9 , wherein said acetyl-CoA carboxylase has reduced activity or expression.
11. The method according to claim 9 , wherein said HMG-CoA reductase has increased activity or expression.
12. The method according to claim 9 , wherein said squalene epoxidase has reduced activity or expression.
13. The method according to claim 9 , wherein said squalene synthase or ATP citrate lyase has increased activity or expression.
14. The method according to claim 9 , wherein said ATP citrate synthase has increased activity or expression.
15. The method according to claim 9 , wherein said mevalonate kinase has increased activity or expression.
16. The method according to claim 9 , wherein said glycerol kinase has increased activity or expression.
17. The method according to claim 9 , wherein said 5-aminolevulinate synthase has reduced activity or expression.