生物技术通报 ›› 2020, Vol. 36 ›› Issue (8): 69-78.doi: 10.13560/j.cnki.biotech.bull.1985.2020-0033

• 研究报告 • 上一篇    下一篇

GLN1基因过表达对提高酿酒酵母糠醛耐受性的研究

吴宇, 王金华, 赵筱   

  1. 湖北工业大学生物工程与食品学院,武汉 430068
  • 收稿日期:2020-01-07 出版日期:2020-08-26 发布日期:2020-08-27
  • 作者简介:吴宇,男,硕士研究生,研究方向:生物资源与环境工程;E-mail:409419891@qq.com
  • 基金资助:
    湖北省自然科学基金项目(2015CFB637),湖北工业大学科研启动基金(BSQD12143)

Enhanced Furfural Tolerance in Saccharomyces cerevisiae by the Overexpression of GLN1 Gene

WU Yu, WANG Jin-hua, ZHAO Xiao   

  1. School of Food and Biological Engineering,Hubei University of Technology,Wuhan 430068
  • Received:2020-01-07 Published:2020-08-26 Online:2020-08-27

摘要: 糠醛是秸秆水解液的主要抑制物,能抑制酿酒酵母的生长和发酵性能。通过将酿酒酵母自身的谷氨酰胺合成酶基因GLN1插入载体pESC-URA,再导入原始酵母BY4741中以构建重组酵母YEA9,并对其糠醛耐受性及发酵性能进行测定。结果表明,在1.55 g/L糠醛浓度下,YEA9的生物量较BY4741提高了3.7倍,耗糖速率提高了8.6倍,最终乙醇浓度提高了9.2倍,糖醇转化率提高了10.6%,且谷胱甘肽含量提高了22.4%,NADH氧化酶酶活提高了5.1%,NAD+/NADH的数值无明显变化,且活性氧(ROS)的水平低于BY4741。在模拟水解液中,YEA9的生物量较BY4741提高了1.75倍,耗糖速率提高了6.1倍,最终乙醇含量提高了5.3倍,糖醇转化率提高了0.5%。综上,过表达GLN1基因能够提高酿酒酵母中谷氨酰胺合成酶酶活,增加谷氨酰胺和谷胱甘肽的含量,使得NADH氧化酶的酶活提高,降低ROS的积累,最终增强酿酒酵母的糠醛胁迫耐受能力和乙醇发酵效率。

关键词: 糠醛, 酿酒酵母, 秸秆水解液, 纤维乙醇, 发酵

Abstract: Furfural is the main inhibitor of straw hydrolysate,and it can inhibit the growth and fermentation performance of Saccharomyces cerevisiae. The glutamine synthetase gene GLN1 of S. cerevisiae was inserted into the vector pESC-URA,and then introduced into the original yeast BY4741 to construct the recombinant yeast YEA9,and its furfural tolerance and fermentation performance were measured. The results showed that at a concentration of 1.55 g / L furfural,the biomass of YEA9 increased by 3.7 times,the sugar consumption rate increased by 8.6 times,the final ethanol concentration increased by 9.2 times,and the sugar alcohol conversion rate increased by 10.6%. Glutathione content increased by 22.4%,NADH oxidase activity increased by 5.1%,NAD + / NADH values did not change significantly,and the level of reactive oxygen species was lower than that in BY4741. In the simulated hydrolysate,the biomass of YEA9 increased by 1.75 times,the sugar consumption rate increased by 6.1 times,the final ethanol content increased by 5.3 times,and the sugar alcohol conversion rate increased by 0.5%. In summary,overexpression of the GLN1 gene can increase the enzyme activity of glutamine synthetase in S. cerevisiae,the content of glutamine and glutathione,and the enzyme activity of NADH oxidase,while reduce the accumulation of ROS,and ultimately enhance the furfural stress tolerance and ethanol fermentation efficiency.

Key words: furfural, Saccharomyces cerevisiae, straw hydrolysate, fiber ethanol, fermentation