論文

査読有り
2018年

Overexpression of PkINO1 improves ethanol resistance of Pichia kudriavzevii N77-4 isolated from the Korean traditional fermentation starter nuruk

Journal of Bioscience and Bioengineering
  • Minetaka Sugiyama
  • ,
  • Seong Yeol Baek
  • ,
  • Shohei Takashima
  • ,
  • Natsumi Miyashita
  • ,
  • Kei Ishida
  • ,
  • Jiyoung Mun
  • ,
  • Soo-Hwan Yeo

126
6
開始ページ
682
終了ページ
689
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.1016/j.jbiosc.2018.06.001
出版者・発行元
Elsevier B.V.

The yeast Pichia kudriavzevii N77-4 was isolated from the Korean traditional fermentation starter nuruk. In this study, fermentation performance and stress resistance ability of N77-4 was analyzed. N77-4 displayed superior thermotolerance (up to 44°C) in addition to enhanced acetic acid resistance compared to Saccharomyces cerevisiae. Moreover, N77-4 produced 7.4 g/L of ethanol with an overall production yield of 0.37 g/g glucose in 20 g/L glucose medium. However, in 250 g/L glucose medium the growth of N77-4 slowed down when the concentration of ethanol reached 14 g/L or more and ethanol production yield also decreased to 0.30 g/g glucose. An ethanol sensitivity test indicated that N77-4 was sensitive to the presence of 1% ethanol, which was not the case for S. cerevisiae. Furthermore, N77-4 displayed a severe growth defect in the presence of 6% ethanol. Because inositol biosynthesis is critical for ethanol resistance, expression levels of the PkINO1 encoding a key enzyme for inositol biosynthesis was analyzed under ethanol stress conditions. We found that ethanol stress clearly repressed PkINO1 expression in a dose-dependent manner and overexpression of PkINO1 improved the growth of N77-4 by 19% in the presence of 6% ethanol. Furthermore, inositol supplementation also enhanced the growth by 13% under 6% ethanol condition. These findings indicate that preventing downregulation in PkINO1 expression caused by ethanol stress improves ethanol resistance and enhances the utility of P. kudriavzevii N77-4 in brewing and fermentation biotechnology.

リンク情報
DOI
https://doi.org/10.1016/j.jbiosc.2018.06.001
ID情報
  • DOI : 10.1016/j.jbiosc.2018.06.001
  • ISSN : 1347-4421
  • ISSN : 1389-1723
  • SCOPUS ID : 85049110548

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