Garrigós Víctor, Matallana Emilia, Picazo Cecilia, Aranda Agustín
Institute for Integrative Systems Biology (I2SysBio), Universitat de València-CSIC, Paterna, Valencia, Spain.
Microb Biotechnol. 2025 May;18(5):e70154. doi: 10.1111/1751-7915.70154.
Trehalose metabolism plays a crucial role in yeast stress tolerance during biomass propagation and dehydration, but its regulatory mechanisms under these industrial conditions remain incompletely understood. This study analyses the role of an antioxidant enzyme, the cytosolic peroxiredoxin Tsa1, in modulating trehalose metabolism in Saccharomyces cerevisiae wine strains during biomass production in molasses. Through comparative analyses in three commercial genetic backgrounds (L2056, T73, EC1118), we demonstrate that TSA1 deletion generally leads to increased intracellular trehalose accumulation despite phenotypic variability among strains. Enzymatic assays revealed that Tsa1 does not regulate trehalose synthesis by altering glycolytic/gluconeogenic flux through pyruvate kinase. However, the deletion of TSA1 resulted in increased oxidation of trehalose synthesis enzymes, as well as enhanced activity of trehalose-6-phosphate synthase and the trehalases Nth1 and Ath1, suggesting the involvement of peroxiredoxin in the futile cycle of trehalose synthesis and degradation. Scaling up the yeast biomass propagation process to semi-industrial conditions confirmed these findings, with increased trehalose levels in the tsa1∆ mutant correlating with enhanced desiccation resistance of the resulting biomass. These results highlight a novel Tsa1-dependent regulatory mechanism governing trehalose metabolism beyond its canonical antioxidant role. Understanding this pathway provides new insights into optimising yeast biomass propagation for industrial applications.
海藻糖代谢在酵母生物量增殖和脱水过程中的应激耐受性方面起着关键作用，但其在这些工业条件下的调控机制仍未完全明晰。本研究分析了一种抗氧化酶——胞质过氧化物还原酶Tsa1在糖蜜中酿酒酵母菌株生物量生产过程中调节海藻糖代谢的作用。通过在三种商业遗传背景（L2056、T73、EC1118）下的比较分析，我们证明，尽管各菌株间存在表型差异，但缺失TSA1通常会导致细胞内海藻糖积累增加。酶活性测定表明，Tsa1不会通过改变丙酮酸激酶的糖酵解/糖异生通量来调节海藻糖合成。然而，TSA1的缺失导致海藻糖合成酶的氧化增加，以及海藻糖 - 6 - 磷酸合酶和海藻糖酶Nth1及Ath1的活性增强，这表明过氧化物还原酶参与了海藻糖合成与降解的无效循环。将酵母生物量增殖过程扩大到半工业条件下证实了这些发现，tsa1∆突变体中海藻糖水平的增加与所得生物量的抗干燥能力增强相关。这些结果突出了一种新的依赖Tsa1的调控机制，该机制在海藻糖代谢中发挥作用，超越了其经典的抗氧化作用。了解这一途径为优化工业应用中的酵母生物量增殖提供了新的见解。
