硫酸锌添加对酿酒酵母乙酸胁迫条件下全局基因转录的影响

Impact of zinc sulfate supplementation on global gene expression profiling of Saccharomyces cerevisiae in response to acetic acid stress

摘要:

【目的】利用转录组测序研究硫酸锌添加提高絮凝酿酒酵母SPSC01乙酸胁迫耐性的分子机理。【方法】在10.0 g/L乙酸胁迫条件下，添加0.03 g/L硫酸锌，取对数期酿酒酵母细胞，与不添加硫酸锌的对照组细胞进行比较转录组分析。【结果】添加硫酸锌的实验组与对照组相比较，50个基因转录水平上调，162个基因转录水平下调，这些转录水平变化明显的基因涉及糖代谢、甲硫氨酸合成、维生素合成等多条代谢途径，此外，转录水平变化的基因还包括抗氧化酶基因等关键胁迫响应基因。【结论】硫酸锌添加可改变酿酒酵母全局基因转录水平，提高抗氧化酶及其他胁迫耐性相关基因的表达，影响细胞氧化还原平衡和能量代谢，通过对多基因转录的调控提高酿酒酵母乙酸耐受性。

Abstract:

[Objective] To study the molecular mechanisms underlying improved acetic acid stress tolerance of the flocculating yeast Saccharomyces cerevisiae SPSC01 by zinc sulfate supplementation. [Methods] Global gene expression profiling was studied by comparative transcriptomic analysis using yeast cells of the log phase cells that were grown with or without 0.03 g/L zinc sulfate addition in the presence of 10.0 g/L acetic acid. [Results] Transcription levels of 50 genes were up-regulated and 162 genes were down-regulated when zinc sulfate was added in the fermentation medium. Genes involved in carbohydrate metabolism, methionine synthesis, and vitamin biosynthesis were up-regulated. In addition, genes encoding the antioxidant enzymes and other stress responsive genes were also up-regulated. [Conclusion] Zinc sulfate addition affected global gene transcription of S. cerevisiae, exerting positive effects on the expression of antioxidant enzymes, stress tolerance and redox balance, as well as energy metabolism. Our results indicate that zinc sulfate supplementation improves acetic acid tolerance of S. cerevisiae by regulating multiple genes and metabolic pathways.