Specific alleles important for ethanol tolerance

Patent metadata

Field	Value
Publication number	US-9862957-B2
Application number	US-201615200542-A
Country	US
Kind code	B2
Filing date	Jul 1, 2016
Priority date	Jun 21, 2011
Publication date	Jan 9, 2018
Grant date	Jan 9, 2018

Abstract

The present disclosure relates to the identification of a QTL associated with high ethanol tolerance in Saccharomyces spp. More specifically, it relates to specific alleles of MKT1 and APJ1 possibly combined with a specific allele of SWS2 that are important in obtaining a high ethanol tolerance in Saccharomyces spp. It relates further to the use of such alleles in the construction of high ethanol tolerant strains, and the use of these alleles in screening for ethanol tolerance.

First claim

What is claimed is:

1. An ethanol tolerant yeast comprising:
a mutant MKT1 allele; and
an overexpressed wild-type yeast SWS2 allele,
wherein said mutant MKT1 encodes a protein consisting of an amino acid residue substitution of a glycine at a position corresponding to position 30 and an arginine at a position corresponding to position 453 of the amino acid sequence set forth in SEQ ID NO: 1; and wherein said ethanol tolerant yeast has a higher ethanol tolerance than a yeast without said mutant MKT1 allele and said overexpressed wild-type SWS2 allele.

2. The ethanol tolerant yeast of claim 1 , wherein said yeast is a diploid, a polyploid, or a aneuploid strain and at least one copy of the MKT1 gene is said mutant MKT1 allele.

3. The ethanol tolerant yeast of claim 1 , wherein said yeast is selected from the group consisting of Saccharomyces, Zygosaccharomyces , and Brettanomyces.

4. The ethanol tolerant yeast of claim 3 , wherein said yeast is a Saccharomyces cerevisiae.

5. The ethanol tolerant yeast of claim 4 , wherein said mutant MKT1 allele encodes a protein comprising the amino acid sequence of SEQ ID NO: 1.

6. The ethanol tolerant yeast of claim 4 , wherein said wild-type yeast SWS2 allele encodes a protein comprising the amino acid sequence of SEQ ID NO: 4.

7. The ethanol tolerant yeast of claim 5 , wherein said wild-type yeast SWS2 allele encodes a protein comprising the amino acid sequence of SEQ ID NO: 4.

8. The ethanol tolerant yeast of claim 2 , wherein said yeast is selected from the group consisting of Saccharomyces, Zygosaccharomyces , and Brettanomyces.

9. The ethanol tolerant yeast of claim 8 , wherein said yeast is a Saccharomyces cerevisiae.

10. The ethanol tolerant yeast of claim 9 , wherein said mutant MKT1 allele encodes a protein comprising the amino acid sequence of SEQ ID NO: 1.

11. The ethanol tolerant yeast of claim 9 , wherein said wild-type yeast SWS2 allele encodes a protein comprising the amino acid sequence of SEQ ID NO: 4.

12. The ethanol tolerant yeast of claim 10 , wherein said wild-type yeast SWS2 allele encodes a protein comprising the amino acid sequence of SEQ ID NO: 4.

13. The ethanol tolerant yeast of claim 1 , further comprising an inactivated yeast APJ1 allele.

14. The ethanol tolerant yeast of claim 2 , further comprising an inactivated yeast APJ1 allele.

15. The ethanol tolerant yeast of claim 3 , further comprising an inactivated yeast APJ1 allele.

16. The ethanol tolerant yeast of claim 4 , further comprising an inactivated yeast APJ1 allele.

17. The ethanol tolerant yeast of claim 5 , further comprising an inactivated yeast APJ1 allele.

18. The ethanol tolerant yeast of claim 6 , further comprising an inactivated yeast APJ1 allele.

19. The ethanol tolerant yeast of claim 1 , wherein said yeast is able to grow on plates with at least 14% ethanol.

20. A process for producing ethanol comprising culturing the ethanol tolerant yeast under conditions to produce ethanol.

Assignees

• Vib Vzw
• Univ Leuven Kath
• Univ Leuven Kath

Inventors

• Thevelein Johan
• Foulquie-Moreno Maria Remedios
• Goovaerts Annelies
• Swinnen Steve

Classifications

• C12N15/81 Primary

  for yeasts · CPC title

• C12Q2600/156

  Polymorphic or mutational markers · CPC title

• C12Q1/025 Primary

  for testing or evaluating the effect of chemical or biological compounds, e.g. drugs, cosmetics (antimicrobial activity C12Q1/18) · CPC title

• C12P7/06

  Ethanol, i.e. non-beverage · CPC title

• C12N15/815

  for yeasts other than Saccharomyces · CPC title