{"title":"Physiological role of the EHL gene in sake yeast and its effects on quality of sake","authors":"Kazuko Tomonaga , Jumpei Tanaka , Keiji Kiyoshi , Takeshi Akao , Kota Watanabe , Toshimori Kadokura , Shunichi Nakayama","doi":"10.1016/j.jbiosc.2023.12.001","DOIUrl":null,"url":null,"abstract":"<div><p>The <em>EHL1/2/3</em> genes were identified by whole-genome sequencing of Kyokai No. 7 (K7), which is a well-known representative Japanese sake yeast <span><span>Saccharomyces cerevisiae</span></span><span>. 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 </span><em>ehl1/2/3</em><span> 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 </span><em>EHL1/2/3</em><span> genes on sake quality. Metabolome analysis and vitamin requirement testing revealed that the </span><em>EHL1/2/3</em> genes are partly responsible for the synthesis of pantothenate. For fermentation profiles, ethanol production by the <em>ehl1/2/3</em> mutant was comparable with that of strain H3, but succinate production was decreased in the <em>ehl1/2/3</em><span> 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 </span><em>ehl1/2/3</em> mutant strain were decreased compared to those of strain H3 during sake brewing. Thus, the <em>EHL1/2/3</em> genes did not affect ethanol production but did affect the production of organic acids and aromatic components during sake brewing.</p></div>","PeriodicalId":15199,"journal":{"name":"Journal of bioscience and bioengineering","volume":null,"pages":null},"PeriodicalIF":2.3000,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of bioscience and bioengineering","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S138917232300350X","RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"BIOTECHNOLOGY & APPLIED MICROBIOLOGY","Score":null,"Total":0}
引用次数: 0
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.
期刊介绍:
The Journal of Bioscience and Bioengineering is a research journal publishing original full-length research papers, reviews, and Letters to the Editor. The Journal is devoted to the advancement and dissemination of knowledge concerning fermentation technology, biochemical engineering, food technology and microbiology.