乙醇胁迫下酿酒酵母(Sc131)生长状态和基因的表达

The Growth Status and Gene Expression of Saccharomyces cerevisiae 131 under Ethanol Stress

为了探究果酒发酵酵母菌混合培养条件下酿酒酵母菌(Sc131)细胞行为变化的分子机制,考察乙醇胁迫条件下菌株Sc131细胞生长状态和基因的表达,建立3%,6%和10%乙醇胁迫酿酒酵母体系。通过分光光度法检测Sc131生长状态,SYBR GREEN实时荧光定量PCR检测醇酰基转移酶EHT1和EEB1基因,转醛醇酶TAL1和NQM1基因,乙醇脱氢酶ADH1基因和乙醛脱氢酶ALD2基因表达量。结果表明,低浓度乙醇胁迫下Sc131细胞生长状态差异不显著。然而,醇酰基转移酶EEB1基因、乙醇脱氢酶ADH1基因和乙醛脱氢酶ALD2基因在乙醇胁迫下的相对表达量都有显著变化。例如:乙醇脱氢酶ADH1基因在10%乙醇胁迫下的相对表达量达到对照组的9 000倍。

In order to explore the molecular mechanism of characteristic changes of cell growth and metabolism un- der the mixed culture of Saccharomyces cerevisiae 131 （Sc131） and non-Saccharomyces cerevisiae, and the influences of cell growth and gene expression were investigated in this study. The culture system of Sc131 was established under the 3% ,6% and 10% ethanol stress, respectively. Aiming to illustrate how the growth status and gene expression of the strain tested under ethanol stress, the growth status was detected with spectrophotometry, and the expression level of al- cohol aeyltransferase genes EHT1 and EEB1, aldol enzyme gene TALI and NQMI, alcohol dehydrogenase gene ADH1 and aldehyde debydrogenase gene ALD2 from Se131 was also detected with SYBR Green I RT-qPCR technique, respec- tively. The results showed that there was some difference between the cell growth status of Sc131 under 3%, 6% and 10% ethanol stress. Moreover, ethanol stress had significant effects on the expression level of alcohol acyltransferase gene EEB1, alcohol dehydrogenase gene ADHI and aldehyde dehydrogenase gene ALD2. For example, the gene expression level of ADH1 gene under 10% ethanol stress could reach approximately 9 000 times higher than that of control group. The present work provides a basis for further study of the molecular mechanism which affects the growth and metabolism of Saccharomyces cerevisiae under the ethanol stress.