College of Biological and Chemical Engineering, Guangxi University of Science and Technology, Liuzhou, 545006, China.
Guangxi Key Laboratory of Green Processing of Sugar Resources, Liuzhou, 545006, China.
World J Microbiol Biotechnol. 2022 Jan 6;38(2):34. doi: 10.1007/s11274-021-03222-z.
Formic acid is a representative small molecule acid in lignocellulosic hydrolysate that can inhibit the growth of Saccharomyces cerevisiae cells during alcohol fermentation. However, the mechanism of formic acid cytotoxicity remains largely unknown. In this study, RNA-Seq technology was used to study the response of S. cerevisiae to formic acid stress at the transcriptional level. Scanning electron microscopy and Fourier transform infrared spectroscopy were conducted to observe the surface morphology of yeast cells. A total of 1504 genes were identified as being differentially expressed, with 797 upregulated and 707 downregulated genes. Transcriptomic analysis showed that most genes related to glycolysis, glycogen synthesis, protein degradation, the cell cycle, the MAPK signaling pathway, and redox regulation were significantly induced under formic acid stress and were involved in protein translation and synthesis amino acid synthesis genes were significantly suppressed. Formic acid stress can induce oxidative stress, inhibit protein biosynthesis, cause cells to undergo autophagy, and activate the intracellular metabolic pathways of energy production. The increase of glycogen and the decrease of energy consumption metabolism may be important in the adaptation of S. cerevisiae to formic acid. In addition, formic acid can also induce sexual reproduction and spore formation. This study through transcriptome analysis has preliminarily reveal the molecular response mechanism of S. cerevisiae to formic acid stress and has provided a basis for further research on methods used to improve the tolerance to cell inhibitors in lignocellulose hydrolysate.
甲酸是木质纤维素水解物中具有代表性的小分子酸，它会在酒精发酵过程中抑制酿酒酵母细胞的生长。然而，甲酸细胞毒性的机制在很大程度上仍然未知。在这项研究中，使用 RNA-Seq 技术研究了酿酒酵母对甲酸胁迫的转录水平响应。通过扫描电子显微镜和傅里叶变换红外光谱观察酵母细胞的表面形态。共鉴定出 1504 个差异表达基因，其中 797 个上调，707 个下调。转录组分析表明，大多数与糖酵解、糖原合成、蛋白质降解、细胞周期、MAPK 信号通路和氧化还原调节相关的基因在甲酸胁迫下显著诱导，参与蛋白质翻译和合成氨基酸合成的基因显著受到抑制。甲酸胁迫会引起氧化应激，抑制蛋白质生物合成，导致细胞自噬，并激活细胞内的能量产生代谢途径。糖原的增加和能量消耗代谢的减少可能在酿酒酵母适应甲酸中起重要作用。此外，甲酸还可以诱导有性生殖和孢子形成。本研究通过转录组分析，初步揭示了酿酒酵母对甲酸胁迫的分子响应机制，为进一步研究提高木质纤维素水解物中细胞抑制剂耐受性的方法提供了依据。
