Biotechnol Bioeng 2021 May 2. Epub 2021 May 2.
State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China.
During continuous very-high-gravity (VHG) ethanol fermentation with Saccharomyces cerevisiae, the process exhibits sustained oscillation in residual glucose, ethanol and biomass, raising a question: how do yeast cells respond to this phenomenon? In this work, the oscillatory behavior of yeast cells was characterized through transcriptome and metabolome analysis for one complete oscillatory period. By analyzing the accumulation of 26 intracellular metabolites and the expression of 90 genes related to central carbon metabolism and stress response, we confirmed that the process oscillation was attributed to intracellular metabolic oscillation with phase difference, and the expression of HXK1, HXT1,2,4 and PFK1 was significantly different from other genes in the Embden-Meyerhof-Parnas pathway, indicating that glucose transport and phosphorylation could be key nodes for regulating the intracellular metabolism under oscillatory conditions. Moreover, the expression of stress response genes was triggered and affected predominately by ethanol inhibition in yeast cells. Read More