TOR1基因缺失对酿酒酵母耐受性的影响

酿酒酵母是最常见且应用最为广泛的酵母菌种,是以糖质和淀粉质为原料的乙醇发酵最经典的菌株.在发酵过程中,有很多不可避免的胁迫环境如高温条件、高渗条件等出现,这些胁迫会阻碍细胞生长并降低细胞的发酵能力,给发酵行业带来一定的经济损失.因此,为改善菌种的耐受性,该研究主要以实验室现有菌株AY12a为亲本菌株,URA3基因作筛选...

Effects of TOR1 gene deletion on the tolerance of Saccharomyces cerevisiae

Saccharomyces cerevisiae is the most common and widely used yeast strain,and it is the most classic strain of ethanol fermentation using saccharide and starch as raw materials.Yeasts are confronted with several inevitable environmental stresses such as hyper-osmotic stress,high temperature,which can negatively affect yeast growth rate and fermentation performance.This will cause some economic losses in related fermentation industry.In order to improve stress tolerance,strain AY12a was used as the starting strain,the URA3 gene was used as a screening marker,and the long primer knockout method was used to realize the gene deletion in this study.Finally,the mutant strain AY12a-tor1Δwas successfully constructed.Tolerance determination of yeast showed that AY12a-tor1Δhad certain high temperature resistance,oxidation environment tolerance and had certain tolerance under other stress conditions.AY12a-tor1Δand AY12a were participated in high-temperature concentrated fermentation of corn,and the alcohol content,residual sugar,48h cell survival rate,CO 2 weight loss and fermentation time after fermentation were determined.The results showed that the ethanol yield of the mutant strain AY12a-tor1Δincreased,the residual sugar content decreased,the cell survival rate did not decrease at 48 h,and the fermentation time was prolonged.