Polypeptide and yeast cell compositions and methods of using the same

Patent metadata

Field	Value
Publication number	US-11028402-B2
Application number	US-201916378106-A
Country	US
Kind code	B2
Filing date	Apr 8, 2019
Priority date	Apr 6, 2018
Publication date	Jun 8, 2021
Grant date	Jun 8, 2021

Abstract

Polypeptides comprising maltose/maltotriose transporters are provided. Additionally, polynucleotides, DNA constructs, and vectors encoding a maltose/maltotriose transporter, or yeast cells harboring such polynucleotides are provided. The yeast cell may be a Saccharomyces eubayanus cell modified to increase the expression or transport activity of a maltose/maltotriose transporter at the plasma membrane of the cell. Further, methods are provided for making a fermentation product by culturing any one of the yeast cells described herein with a fermentable substrate. Finally, methods are provided to select for and isolate maltotriose-utilizing strains of Saccharomyces eubayanus.

First claim

We claim:

1. A polynucleotide encoding a polypeptide comprising at least 95% sequence identity to SEQ ID NO: 4 and comprising at least six amino acid substitutions to SEQ ID NO: 4 at positions selected from the group consisting of S468, I503, G504, N505, V508, I512, N522, F534, L536, V538, and I540; or a functional fragment of the polypeptide thereof, wherein the polypeptide or functional fragment thereof has maltotriose transporter activity.

2. The polynucleotide of claim 1 , wherein the polynucleotide comprises SEQ ID NO: 9.

3. A DNA construct comprising a promoter operably linked to the polynucleotide of claim 1 .

4. A vector comprising the DNA construct of claim 3 .

5. A Saccharomyces yeast cell comprising the polynucleotide of claim 1 .

6. A Saccharomyces yeast cell modified to increase as compared to a control yeast cell the expression or maltose/maltotriose transport activity of a maltose/maltotriose transporter polypeptide, wherein the yeast cell comprises a polynucleotide encoding a polypeptide having at least 95% sequence identity to SEQ ID NO: 4 and comprising at least six amino acid substitutions to SEQ ID NO: 4, wherein the amino acid substitutions are at positions selected from the group consisting of S468, I503, G504, N505, V508, I512, N522, F534, L536, V538, and I540, or a functional fragment thereof having maltotriose transporter activity.

7. The yeast cell of claim 6 , wherein the increased expression or increased maltose/maltotriose transport activity of the maltose/maltotriose transporter polypeptide is at the plasma membrane of the yeast cell.

8. The yeast cell of claim 6 , wherein the expression or maltose/maltotriose transport activity of the maltose/maltotriose transporter polypeptide is increased by at least 30% as compared to the control yeast cell.

9. The yeast cell of claim 6 , wherein the yeast cell is selected from the species consisting of Saccharomyces eubayanus, Saccharomyces cerevisiae, Saccharomyces paradoxus, Saccharomyces mikatae, Saccharomyces arboricola, Saccharomyces kudriavzevii, Saccharomyces jurei, and Saccharomyces uvarum.

10. A method for making a fermentation product comprising culturing the yeast cells of claim 5 with a fermentable substrate to produce the fermentation product.

11. The method of claim 10 , wherein the fermentable substrate comprises wort or malt extract.

12. The method of claim 10 , wherein the fermentation product is selected from the group consisting of a beer product, a wine product, an alcoholic beverage, a biochemical, and a biofuel.

Assignees

• Wisconsin Alumni Res Found

Inventors

• Hittinger Chris Todd
• Baker Emilyclare Patricia

Classifications

• C12P7/00

  Preparation of oxygen-containing organic compounds · CPC title

• C07K14/395

  from Saccharomyces · CPC title

• C12C11/00 Primary

  Fermentation processes for beer (preparation of wine C12G1/00) · CPC title

• C12N1/16

  Yeasts; Culture media therefor · CPC title

• C12G1/0203

  by microbiological or enzymatic treatment · CPC title