酿酒酵母在乳酸胁迫下的应激响应及转录组学分析OA

Lactic acid could inhibit the growth and metabolism of microorganisms to a certain extent.To explore the response of Sac-charomyces cerevisiae under lactic acid stress,this study employed S.cerevisiae strain N85 as the experimental subject to systematically in-vestigate the effects of lactic acid stress on the growth and physiological characteristics of the yeast cells.The transcriptomes of yeast under lactic acid stress were further employed to reveal the differential gene expressions and the related metabolic pathways of the response of S.cerevisiae under lactic acid conditions.Results showed that lactic acid inhibited the growth of S.cerevisiae,with higher concentrations lead-ing to more pronounced inhibition.After lactic acid treatment,the surface morphology of yeast cells was disrupted and the cell membrane permeability was increased,resulting in elevated leakage of intracellular nucleic acids and proteins,as well as increased extracellular ATP levels.The results of transcriptomic sequencing suggested that,a total of 1 757 differentially expressed genes(DEGs)were identified in the yeast cells cultured under lactic acid conditions compared with those grew in YPD medium.These DEGs were mainly enriched in key pathways of lactic acid metabolism,such as ribosome biosynthesis,tricarboxylic acid cycle,pyruvate metabolism,glycolysis/gluconeogen-esis,oxidative phosphorylation,and amino acid metabolism.The current study enhances the understanding of the molecular response mechanism of S.cerevisiae under lactic acid stress and provides a theoretical basis for the genetic modification of S.cerevisiae to improve its lactic acid tolerance.