Ethanol, as one of the most important biological fuels, is mainly produced by Saccharomyces cerevisiae. But with the accumulation of ethanol, the viability and growth of Saccharomyces cerevisiae is often stressed during fermentation. At present, the reaction mechanism of Saccharomyces cerevisiae to ethanol stress has not been fully elucidated. In this paper, a metabolomics approach with gas chromatography-mass spectrometry was performed to investigate the metabolic changes of Saccharomyces cerevisiae cultured with 0%, 2% and 5% ethanol. The results of partial least-squares discriminant analysis (PLS-DA) clearly reflected the metabolic variations induced by ethanol stress. It was found that in total 36 metabolites changed significantly with univariate analysis, including amino acids, organic acids, and fatty acids. The citrate cycle and alanine, aspartate and glutamate metabolism were found as the markedly perturbed metabolic pathways. Significant alterations of metabolites in these pathways (succinic acid, citric acid, pyruvate, fumarate, glutamate, aspartate, alanine) indicated that ethanol stress impeded the citrate cycle at the node of citrate. This might cause insufficient energy supply of the cell and the synthesis reduction of some amino acids and other substrates. Furthermore, the growth of the cell was slowed down. These results demonstrated that metabolomics has potential to reveal the regulation mechanisms for ethanol stress in Saccharomyces cerevisiae.

中文翻译：

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酿酒酵母对乙醇胁迫的代谢反应采用气相色谱-质谱联用。

乙醇是最重要的生物燃料之一，主要由酿酒酵母生产。但是随着乙醇的积累，在发酵过程中常常强调酿酒酵母的生存能力和生长。目前，酿酒酵母对乙醇胁迫的反应机理尚未完全阐明。本文采用气相色谱-质谱联用的代谢组学方法研究了0％，2％和5％乙醇培养的酿酒酵母的代谢变化。偏最小二乘判别分析（PLS-DA）的结果清楚地反映了乙醇胁迫引起的代谢变化。结果发现，通过单变量分析，总共36种代谢物发生了显着变化，包括氨基酸，有机酸和脂肪酸。柠檬酸盐循环和丙氨酸，发现天冬氨酸和谷氨酸代谢是显着干扰的代谢途径。这些途径中的代谢物（琥珀酸，柠檬酸，丙酮酸，富马酸，谷氨酸，天冬氨酸，丙氨酸）的显着变化表明乙醇胁迫阻碍了柠檬酸结点的柠檬酸循环。这可能会导致细胞能量供应不足以及某些氨基酸和其他底物的合成减少。此外，细胞的生长减慢了。这些结果表明，代谢组学有可能揭示酿酒酵母中乙醇胁迫的调节机制。丙氨酸）表明乙醇胁迫阻碍了柠檬酸盐节点的柠檬酸盐循环。这可能会导致细胞能量供应不足以及某些氨基酸和其他底物的合成减少。此外，细胞的生长减慢了。这些结果表明，代谢组学有潜力揭示酿酒酵母中乙醇胁迫的调节机制。丙氨酸）表明乙醇胁迫阻碍了柠檬酸盐节点的柠檬酸盐循环。这可能会导致细胞能量供应不足以及某些氨基酸和其他底物的合成减少。此外，细胞的生长减慢了。这些结果表明，代谢组学有潜力揭示酿酒酵母中乙醇胁迫的调节机制。