Isolation, Identification, and Characterization of an Acid-Tolerant Pichia kudriavzevii and Exploration of Its Acetic Acid Tolerance Mechanism

Pichia kudriavzevii is one of the major non-Saccharomyces cerevisiae yeasts in Chinese baijiu brewing, which has shown a substantially higher tolerance to acid, heat, and ethanol. Exploring mechanism P. could have positive effect on artificially controlled production baijiu. In this study, an efficient acetic-acid-tolerant strain, Y2, was isolated from yellow water strong-flavored brewing waste, its molecular acetic acid investigated through comparative transcriptomic analysis. The strain Y2 tolerate 12 g/L acid. According Kyoto Encyclopedia Genes Genomes (KEGG) pathway enrichment analysis, differentially expressed genes (DEGs) were mainly enriched oxidative phosphorylation, citrate cycle, glycolysis/gluconeogenesis, carbon metabolism under low (AL group) high (AH concentrations However, DEG more profound AH group when compared control. Compared with AL group, expression related phosphorylation significantly upregulated, while terms TCA phosphoenolpyruvate carboxykinase upregulated both groups positively correlated This followed by synthase, isocitrate dehydrogenase, malate succinate dehydrogenase. These results illustrated possible regulating metabolism-related pathways provided basis for further investigation mechanism.