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Tomonaga K, Tanaka J, Kiyoshi K, Akao T, Watanabe K, Kadokura T, Nakayama S. Physiological role of the EHL gene in sake yeast and its effects on quality of sake. J Biosci Bioeng 2024; 137:195-203. [PMID: 38242756 DOI: 10.1016/j.jbiosc.2023.12.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 11/09/2023] [Accepted: 12/02/2023] [Indexed: 01/21/2024]
Abstract
The EHL1/2/3 genes were identified by whole-genome sequencing of Kyokai No. 7 (K7), which is a well-known representative Japanese sake yeast Saccharomyces cerevisiae. The genes are present in K7, but not in laboratory strain S288C. Although the genes were presumed to encode epoxide hydrolase based on homology analysis, their effect on cellular metabolism in sake yeast has not yet been clarified. We constructed ehl1/2/3 mutants harboring a stop codon in each gene using the haploid yeast strain H3 as the parental strain, which was derived from K701, and investigated the physiological role and effects of the EHL1/2/3 genes on sake quality. Metabolome analysis and vitamin requirement testing revealed that the EHL1/2/3 genes are partly responsible for the synthesis of pantothenate. For fermentation profiles, ethanol production by the ehl1/2/3 mutant was comparable with that of strain H3, but succinate production was decreased in the ehl1/2/3 mutant compared to strain H3 when cultured in yeast malt (YM) medium containing 10% glucose and during sake brewing. Ethyl hexanoate and isoamyl acetate levels in the ehl1/2/3 mutant strain were decreased compared to those of strain H3 during sake brewing. Thus, the EHL1/2/3 genes did not affect ethanol production but did affect the production of organic acids and aromatic components during sake brewing.
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Affiliation(s)
- Kazuko Tomonaga
- Department of Fermentation Science and Technology, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Jumpei Tanaka
- Department of Fermentation Science and Technology, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Keiji Kiyoshi
- Department of Biochemistry and Applied Bioscience, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadainishi, Miyazaki-shi, Miyazaki 889-2192, Japan
| | - Takeshi Akao
- National Research Institute of Brewing, 3-7-1 Kagamiyama, Higashi-hiroshima, Hiroshima 739-0046, Japan
| | - Kota Watanabe
- Department of Fermentation Science and Technology, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Toshimori Kadokura
- Department of Fermentation Science and Technology, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Shunichi Nakayama
- Department of Fermentation Science and Technology, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan.
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Takase S, Tomonaga K, Tanaka J, Moriya C, Kiyoshi K, Akao T, Watanabe K, Kadokura T, Nakayama S. The bio3 mutation in sake yeast leads to changes in organic acid profiles and ester levels but not ethanol production. J Biosci Bioeng 2023:S1389-1723(23)00115-9. [PMID: 37183145 DOI: 10.1016/j.jbiosc.2023.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 04/19/2023] [Accepted: 04/19/2023] [Indexed: 05/16/2023]
Abstract
Biotin is an essential coenzyme that is bound to carboxylases and participates in fatty acid synthesis. The fact that sake yeast exhibit biotin prototrophy while almost all other Saccharomyces cerevisiae strains exhibit biotin auxotrophy, implies that biotin prototrophy is an important factor in sake brewing. In this study, we inserted a stop codon into the biotin biosynthetic BIO3 gene (cording for 7,8-diamino-pelargonic acid aminotransferase) of a haploid sake yeast strain using the marker-removable plasmid pAUR135 and investigated the fermentation profile of the resulting bio3 mutant. Ethanol production was not altered when the bio3 mutant was cultured in Yeast Malt (YM) medium containing 10% glucose at 15 °C and 30 °C. Interestingly, ethanol production was also not changed during the sake brewing process. On the other hand, the levels of organic acids in the bio3 mutant were altered after culturing in YM medium and during sake brewing. In addition, ethyl hexanoate and isoamyl acetate levels decreased in the bio3 mutant during sake brewing. Metabolome analysis revealed that the decreased levels of fatty acids in the bio3 mutant were attributed to the decreased levels of ethyl hexanoate. Further, the transcription level of genes related to the synthesis of ethyl hexanoate and isoamyl acetate were significantly reduced. The findings indicated that although the decrease in biotin biosynthesis did not affect ethanol production, it did affect the synthesis of components such as organic acids and aromatic compounds. Biotin biosynthesis ability is thus a key factor in sake brewing.
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Affiliation(s)
- Shiori Takase
- Department of Fermentation Science and Technology, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Kazuko Tomonaga
- Department of Fermentation Science and Technology, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Jumpei Tanaka
- Department of Fermentation Science and Technology, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Chise Moriya
- Department of Fermentation Science and Technology, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Keiji Kiyoshi
- Department of Biochemistry and Applied Bioscience, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadainishi, Miyazaki-shi, Miyazaki 889-2192, Japan
| | - Takeshi Akao
- National Research Institute of Brewing, 3-7-1 Kagamiyama, Higashi-hiroshima, Hiroshima 739-0046, Japan
| | - Kota Watanabe
- Department of Fermentation Science and Technology, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Toshimori Kadokura
- Department of Fermentation Science and Technology, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
| | - Shunichi Nakayama
- Department of Fermentation Science and Technology, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan.
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Negoro H, Ishida H. Development of sake yeast breeding and analysis of genes related to its various phenotypes. FEMS Yeast Res 2022; 22:6825454. [PMID: 36370450 DOI: 10.1093/femsyr/foac057] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 10/21/2022] [Accepted: 11/10/2022] [Indexed: 11/13/2022] Open
Abstract
Sake is a traditional Japanese alcoholic beverage made from rice and water, fermented by the filamentous fungi Aspergillus oryzae and the yeast Saccharomyces cerevisiae. Yeast strains, also called sake yeasts, with high alcohol yield and the ability to produce desired flavor compounds in the sake, have been isolated from the environment for more than a century. Furthermore, numerous methods to breed sake yeasts without genetic modification have been developed. The objectives of breeding include increasing the efficiency of production, improving the aroma and taste, enhancing safety, imparting functional properties, and altering the appearance of sake. With the recent development of molecular biology, the suitable sake brewing characteristics in sake yeasts, and the causes of acquisition of additional phenotypes in bred yeasts have been elucidated genetically. This mini-review summarizes the history and lineage of sake yeasts, their genetic characteristics, the major breeding methods used, and molecular biological analysis of the acquired strains. The data in this review on the metabolic mechanisms of sake yeasts and their genetic profiles will enable the development of future strains with superior phenotypes.
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Affiliation(s)
- Hiroaki Negoro
- Research Institute, Gekkeikan Sake Co. Ltd., 101 Shimotoba-koyanagi-cho, Fushimi-ku, Kyoto 612-8385, Japan
| | - Hiroki Ishida
- Research Institute, Gekkeikan Sake Co. Ltd., 101 Shimotoba-koyanagi-cho, Fushimi-ku, Kyoto 612-8385, Japan
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Negoro H, Kotaka A, Ishida H. Mutation in gene coding for glucose-induced degradation-deficient protein contributes to high malate production in yeast strain No. 28 and No. 77 used for industrial brewing of sake. Biosci Biotechnol Biochem 2021; 85:1283-1289. [PMID: 33686405 DOI: 10.1093/bbb/zbab031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 02/19/2021] [Indexed: 11/13/2022]
Abstract
Saccharomyces cerevisiae produces organic acids including malate during alcohol fermentation. Since malate contributes to the pleasant flavor of sake, high-malate-producing yeast strain No. 28 and No. 77 have been developed by the Brewing Society of Japan. In this study, the genes responsible for the high malate phenotype in these strains were investigated. We had previously found that the deletion of components of the glucose-induced degradation-deficient (GID) complex led to high malate production in yeast. Upon examining GID protein-coding genes in yeast strain No. 28 and No. 77, a nonsense homozygous mutation of GID4 in strain No. 28 and of GID2 in strain No. 77 were identified as the cause of high malate production. Furthermore, complementary tests of these mutations indicated that the heterozygous nonsense mutation in GID2 was recessive. In contrast, the heterozygous nonsense mutation in GID4 was considered semidominant.
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Affiliation(s)
- Hiroaki Negoro
- Research Institute, Gekkeikan Sake Co. Ltd., 101 Shimotoba-koyanagi-cho, Fushimi-ku, Kyoto, Japan
| | - Atsushi Kotaka
- Research Institute, Gekkeikan Sake Co. Ltd., 101 Shimotoba-koyanagi-cho, Fushimi-ku, Kyoto, Japan
| | - Hiroki Ishida
- Research Institute, Gekkeikan Sake Co. Ltd., 101 Shimotoba-koyanagi-cho, Fushimi-ku, Kyoto, Japan
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Fujimaru Y, Kusaba Y, Zhang N, Dai H, Yamamoto Y, Takasaki M, Kakeshita T, Kitagaki H. Extra copy of the mitochondrial cytochrome-c peroxidase gene confers a pyruvate-underproducing characteristic of sake yeast through respiratory metabolism. J Biosci Bioeng 2021; 131:640-646. [PMID: 33597082 DOI: 10.1016/j.jbiosc.2021.01.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 01/23/2021] [Accepted: 01/25/2021] [Indexed: 12/12/2022]
Abstract
The mechanism of pyruvate-underproduction of aneuploid sake yeast was investigated in this study. In our previous report, we revealed that an increase in chromosome XI decreases pyruvate productivity of sake yeast. In this report, we found that increased copy number of CCP1, which is located on chromosome XI and encodes cytochrome-c peroxidase, decreased the pyruvate productivity of sake yeasts. Introducing an extra copy of CCP1 activated respiratory metabolism governed by Hap4 and increased reactive oxygen species. Therefore, it was concluded that increased copy number of CCP1 on chromosome XI activated respiratory metabolism and decreased pyruvate levels in an aneuploid sake yeast. This is the first report that describes a mechanism underlying the improvement of brewery yeast by chromosomal aneuploidy.
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Affiliation(s)
- Yuki Fujimaru
- Graduate School of Health Sciences, Koji Ceramide Research Project, Saga University, 1, Honjo-cho, Saga city, Saga 840-8502, Japan
| | - Yuki Kusaba
- Graduate School of Health Sciences, Koji Ceramide Research Project, Saga University, 1, Honjo-cho, Saga city, Saga 840-8502, Japan
| | - Nairui Zhang
- Graduate School of Health Sciences, Koji Ceramide Research Project, Saga University, 1, Honjo-cho, Saga city, Saga 840-8502, Japan
| | - Huanghuang Dai
- Graduate School of Health Sciences, Koji Ceramide Research Project, Saga University, 1, Honjo-cho, Saga city, Saga 840-8502, Japan
| | - Yuki Yamamoto
- Graduate School of Health Sciences, Koji Ceramide Research Project, Saga University, 1, Honjo-cho, Saga city, Saga 840-8502, Japan
| | - Mitsuhiro Takasaki
- Organization of General Education, Saga University, 1, Honjo-cho, Saga city, Saga 840-8502, Japan
| | - Tetsuro Kakeshita
- Faculty of Science and Engineering, Saga University, 1, Honjo-cho, Saga city, Saga 840-8502, Japan
| | - Hiroshi Kitagaki
- Graduate School of Health Sciences, Koji Ceramide Research Project, Saga University, 1, Honjo-cho, Saga city, Saga 840-8502, Japan.
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Mutation in the peroxin-coding gene PEX22 contributing to high malate production in Saccharomyces cerevisiae. J Biosci Bioeng 2018; 125:211-217. [DOI: 10.1016/j.jbiosc.2017.08.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 08/10/2017] [Accepted: 08/21/2017] [Indexed: 11/22/2022]
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Chromosomal Aneuploidy Improves the Brewing Characteristics of Sake Yeast. Appl Environ Microbiol 2017; 83:AEM.01620-17. [PMID: 28986374 DOI: 10.1128/aem.01620-17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 09/20/2017] [Indexed: 01/02/2023] Open
Abstract
The effect of chromosomal aneuploidy on the brewing characteristics of brewery yeasts has not been studied. Here we report that chromosomal aneuploidy in sake brewery yeast (Saccharomyces cerevisiae) leads to the development of favorable brewing characteristics. We found that pyruvate-underproducing sake yeast, which produces less off-flavor diacetyl, is aneuploid and trisomic for chromosomes XI and XIV. To confirm that this phenotype is due to aneuploidy, we obtained 45 haploids with various chromosomal additions and investigated their brewing profiles. A greater number of chromosomes correlated with a decrease in pyruvate production. Especially, sake yeast haploids with extra chromosomes in addition to chromosome XI produced less pyruvate than euploids. Mitochondrion-related metabolites and intracellular oxygen species in chromosome XI aneuploids were higher than those in euploids, and this effect was canceled in their "petite" strains, suggesting that an increase in chromosomes upregulated mitochondrial activity and decreased pyruvate levels. These findings suggested that an increase in chromosome number, including chromosome XI, in sake yeast haploids leads to pyruvate underproduction through the augmentation of mitochondrial activity. This is the first report proposing that aneuploidy in brewery yeasts improves their brewing profile.IMPORTANCE Chromosomal aneuploidy has not been evaluated in development of sake brewing yeast strains. This study shows the relationship between chromosomal aneuploidy and brewing characteristics of brewery yeast strains. High concentrations of pyruvate during sake storage give rise to α-acetolactate and, in turn, to high concentrations of diacetyl, which is considered an off-flavor. It was demonstrated that pyruvate-underproducing sake yeast is trisomic for chromosome XI and XIV. Furthermore, sake yeast haploids with extra chromosomes produced reduced levels of pyruvate and showed metabolic processes characteristic of increased mitochondrial activity. This novel discovery will enable the selection of favorable brewery yeasts by monitoring the copy numbers of specific chromosomes through a process that does not involve generation/use of genetically modified organisms.
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Negoro H, Kotaka A, Matsumura K, Tsutsumi H, Sahara H, Hata Y. Breeding of high malate‐producing diploid sake yeast with a homozygous mutation in the
VID24
gene. JOURNAL OF THE INSTITUTE OF BREWING 2016. [DOI: 10.1002/jib.366] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Hiroaki Negoro
- Research Institute, Gekkeikan Sake Co. Ltd 101 Shimotoba‐koyanagi‐cho, Fushimi‐ku Kyoto 612‐8385 Japan
| | - Atsushi Kotaka
- Research Institute, Gekkeikan Sake Co. Ltd 101 Shimotoba‐koyanagi‐cho, Fushimi‐ku Kyoto 612‐8385 Japan
| | - Kengo Matsumura
- Research Institute, Gekkeikan Sake Co. Ltd 101 Shimotoba‐koyanagi‐cho, Fushimi‐ku Kyoto 612‐8385 Japan
| | - Hiroko Tsutsumi
- Research Institute, Gekkeikan Sake Co. Ltd 101 Shimotoba‐koyanagi‐cho, Fushimi‐ku Kyoto 612‐8385 Japan
| | - Hiroshi Sahara
- Research Institute, Gekkeikan Sake Co. Ltd 101 Shimotoba‐koyanagi‐cho, Fushimi‐ku Kyoto 612‐8385 Japan
| | - Yoji Hata
- Research Institute, Gekkeikan Sake Co. Ltd 101 Shimotoba‐koyanagi‐cho, Fushimi‐ku Kyoto 612‐8385 Japan
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Negoro H, Kotaka A, Matsumura K, Tsutsumi H, Hata Y. Enhancement of malate-production and increase in sensitivity to dimethyl succinate by mutation of the VID24 gene in Saccharomyces cerevisiae. J Biosci Bioeng 2016; 121:665-671. [DOI: 10.1016/j.jbiosc.2015.11.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 10/23/2015] [Accepted: 11/12/2015] [Indexed: 10/22/2022]
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Sawada K, Kitagaki H. Residual mitochondrial transmembrane potential decreases unsaturated fatty acid level in sake yeast during alcoholic fermentation. PeerJ 2016; 4:e1552. [PMID: 26839744 PMCID: PMC4734444 DOI: 10.7717/peerj.1552] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 12/10/2015] [Indexed: 12/15/2022] Open
Abstract
Oxygen, a key nutrient in alcoholic fermentation, is rapidly depleted during this process. Several pathways of oxygen utilization have been reported in the yeast Saccharomyces cerevisiae during alcoholic fermentation, namely synthesis of unsaturated fatty acid, sterols and heme, and the mitochondrial electron transport chain. However, the interaction between these pathways has not been investigated. In this study, we showed that the major proportion of unsaturated fatty acids of ester-linked lipids in sake fermentation mash is derived from the sake yeast rather than from rice or koji (rice fermented with Aspergillus). Additionally, during alcoholic fermentation, inhibition of the residual mitochondrial activity of sake yeast increases the levels of unsaturated fatty acids of ester-linked lipids. These findings indicate that the residual activity of the mitochondrial electron transport chain reduces molecular oxygen levels and decreases the synthesis of unsaturated fatty acids, thereby increasing the synthesis of estery flavors by sake yeast. This is the first report of a novel link between residual mitochondrial transmembrane potential and the synthesis of unsaturated fatty acids by the brewery yeast during alcoholic fermentation.
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Affiliation(s)
- Kazutaka Sawada
- Department of Biochemistry and Applied Biosciences, United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan; Industrial Technology Center of Saga Prefecture, Saga city, Saga, Japan
| | - Hiroshi Kitagaki
- Department of Biochemistry and Applied Biosciences, United Graduate School of Agricultural Sciences, Kagoshima University, Japan; Department of Environmental Science, Faculty of Agriculture, Saga University, Saga city, Saga, Japan
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Hayakawa K, Kajihata S, Matsuda F, Shimizu H. (13)C-metabolic flux analysis in S-adenosyl-L-methionine production by Saccharomyces cerevisiae. J Biosci Bioeng 2015; 120:532-8. [PMID: 25912448 DOI: 10.1016/j.jbiosc.2015.03.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 02/16/2015] [Accepted: 03/16/2015] [Indexed: 11/28/2022]
Abstract
S-Adenosyl-L-methionine (SAM) is a major biological methyl group donor, and is used as a nutritional supplement and prescription drug. Yeast is used for the industrial production of SAM owing to its high intracellular SAM concentrations. To determine the regulation mechanisms responsible for such high SAM production, (13)C-metabolic flux analysis ((13)C-MFA) was conducted to compare the flux distributions in the central metabolism between Kyokai no. 6 (high SAM-producing) and S288C (control) strains. (13)C-MFA showed that the levels of tricarboxylic acid (TCA) cycle flux in SAM-overproducing strain were considerably increased compared to those in the S228C strain. Analysis of ATP balance also showed that a larger amount of excess ATP was produced in the Kyokai 6 strain because of increased oxidative phosphorylation. These results suggest that high SAM production in Kyokai 6 strains could be attributed to enhanced ATP regeneration with high TCA cycle fluxes and respiration activity. Thus, maintaining high respiration efficiency during cultivation is important for improving SAM production.
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Affiliation(s)
- Kenshi Hayakawa
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan; KANEKA Fundamental Technology Research Alliance Laboratories, Graduate School of Engineering, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Shuichi Kajihata
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Fumio Matsuda
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Hiroshi Shimizu
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871, Japan.
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