Gene capable of improving low temperature fermentability and/or low temperature resistance and use thererof
The present invention relates to a gene capable of improving low temperature performance (low temperature fermentability and/or low temperature resistance) and use thereof, in particular, to a brewery yeast with superior low temperature performance, alcoholic beverages produced using said yeast, and a method for producing said beverages. More particularly, the present invention relates to a yeast, whose low temperature performance is improved by amplifying expression level of DLT1 gene encoding Dltlp capable of improving low temperature performance of a brewery yeast, especially non-ScDLT1 gene specific to a lager brewing yeast, and to a method for producing alcoholic beverages using said yeast.
1 . A polynucleotide selected from the group consisting of:
(a) a polynucleotide comprising a polynucleotide consisting of the nucleotide sequence of SEQ ID NO:1;
(b) a polynucleotide comprising a polynucleotide encoding a protein consisting of the amino acid sequence of SEQ ID NO:2;
(c) a polynucleotide comprising a polynucleotide encoding a protein consisting of the amino acid sequence of SEQ ID NO:2 with one or more amino acids thereof being deleted, substituted, inserted and/or added, and having an activity to improve low temperature performance;
(d) a polynucleotide comprising a polynucleotide encoding a protein having an amino acid sequence having 60% or higher identity with the amino acid sequence of SEQ ID NO:2, and having an activity to improve low temperature performance;
(e) a polynucleotide comprising a polynucleotide which hybridizes to a polynucleotide consisting of a nucleotide sequence complementary to the nucleotide sequence of SEQ ID NO:1 under stringent conditions, and which encodes a protein having an activity to improve low temperature performance; and
(f) a polynucleotide comprising a polynucleotide which hybridizes to a polynucleotide consisting of a nucleotide sequence complementary to the nucleotide sequence of the polynucleotide encoding the protein of the amino acid sequence of SEQ ID NO:2 under stringent conditions, and which encodes a protein having an activity to improve low temperature performance.
2 . The polynucleotide of claim 1 selected from the group consisting of:
(g) a polynucleotide comprising a polynucleotide encoding a protein consisting of the amino acid sequence of SEQ ID NO: 2, or an amino acid sequence of SEQ ID NO: 2 wherein 1 to 10 amino acids thereof is deleted, substituted, inserted, and/or added, and wherein said protein has an activity to improve low temperature performance;
(h) a polynucleotide comprising a polynucleotide encoding a protein having an amino acid sequence which has 90% or higher identity with the amino acid sequence of SEQ ID NO: 2, and having an activity to improve low temperature performance; and
(i) a polynucleotide comprising a polynucleotide consisting of the nucleotide sequence of SEQ ID NO: 1 or a polynucleotide which hybridizes to a polynucleotide consisting of a nucleotide sequence complementary to the nucleotide sequence of SEQ ID NO: 1 under high stringent conditions, and which encodes a protein having an activity to improve low temperature performance.
3 . The polynucleotide of claim 1 comprising a polynucleotide consisting of SEQ ID NO: 1.
4 . The polynucleotide of claim 1 comprising a polynucleotide encoding a protein consisting of SEQ ID NO: 2.
5 . The polynucleotide of claim 1 , wherein the polynucleotide is DNA.
6 . A protein encoded by the polynucleotide of claim 1 .
7 . A vector comprising the polynucleotide of claim 1 .
8 . A yeast, wherein the vector of claim 7 is introduced.
9 . The yeast of claim 8 , whose low temperature performance is improved by introducing the vector comprising the polynucleotide.
10 . The yeast of claim 9 , whose low temperature performance is improved by increasing the expression level of the protein of claim 6 encoded by the polynucleotide.
11 . A method for producing an alcoholic beverage comprising culturing the yeast of claim 8 .
12 . The method for producing an alcoholic beverage of claim 11 , wherein the brewed alcoholic beverage is a malt beverage.
13 . The method for producing an alcoholic beverage of claim 11 , wherein the brewed alcoholic beverage is wine.
14 . An alcoholic beverage produced by the method of claim 11 .
15 . A method for assessing a test yeast for its low temperature performance, comprising using a primer or a probe designed based on a nucleotide sequence of a gene having the nucleotide sequence of SEQ ID NO: 1 and capable of improving low temperature performance.
16 . A method for assessing a test yeast for its low temperature performance, comprising: culturing a test yeast; and measuring an expression level of a gene having the nucleotide sequence of SEQ ID NO: 1 and capable of improving low temperature performance.
17 . A method for selecting a yeast, comprising: culturing test yeasts; quantifying the protein according to claim 6 or measuring an expression level of a gene having the nucleotide sequence of SEQ ID NO: 1 and capable of improving low temperature performance; and selecting a test yeast having said protein amount or said gene expression level according to a target low temperature fermentability.
18 . The method for selecting a yeast according to claim 17 , comprising: culturing a reference yeast and test yeasts; measuring an expression level of a gene having the nucleotide sequence of SEQ ID NO: 1 and capable of improving low temperature performance in each yeast; and selecting a test yeast having the gene expressed higher than that in the reference yeast.
19 . The method for selecting a yeast according to claim 17 , comprising: culturing a reference yeast and test yeasts; quantifying the protein encoded by the polynucleotide in each yeast; and selecting a test yeast having said protein in a larger amount than that in the reference yeast.
20 . A method for producing an alcoholic beverage comprising: conducting fermentation for producing an alcoholic beverage using the yeast according to claim 8 or a yeast selected by the method according to claim 17 ; and improving low temperature performance.