Different Gene Expression Patterns of Hexose Transporter Genes Modulate Fermentation Performance of Four Saccharomyces cerevisiae Strains

Abstract

In Saccharomyces cerevisiae, the fermentation rate and the ability to complete the sugar transformation process depend on the glucose and fructose transporter set-up. Hexose transport mainly occurs via facilitated diffusion carriers and these are encoded by the HXT gene family and GAL2. In addition, FSY1, coding a fructose/H+ symporter, was identified in some wine strains. This little-known transporter could be relevant in the last part of the fermentation process when fructose is the most abundant sugar. In this work, we investigated the gene expression of the hexose transporters during late fermentation phase, by means of qPCR. Four S. cerevisiae strains (P301.9, R31.3, R008, isolated from vineyard, and the commercial EC1118) were considered and the transporter gene expression levels were determined to evaluate how the strain gene expression pattern modulated the late fermentation process. The very low global gene expression and the poor fermentation performance of R008 suggested that the overall expression level is a determinant to obtain the total sugar consumption. Each strain showed a specific gene expression profile that was strongly variable. This led to rethinking the importance of the HXT3 gene that was previously considered to play a major role in sugar transport. In vineyard strains, other transporter genes, such as HXT6/7, HXT8, and FSY1, showed higher expression levels, and the resulting gene expression patterns properly supported the late fermentation process.

An engineered non-oxidative glycolytic bypass based on Calvin-cycle enzymes enables anaerobic co-fermentation of glucose and sorbitol by Saccharomyces cerevisiae

“…However, whole-genome sequencing did not identify such mutations in steady-state chemostat cultures of the PRK-RuBisCO-expressing reference strain IMX1489, which co-consumed sorbitol but did not contain overexpression cassettes for HXT15 and SOR15 . Gene expression patterns in S. cerevisiae are strain dependent [ 41 ] and glucose concentrations strongly affect transcriptional regulation of HXT transporter genes [ 37 ]. Furthermore, expression of HXT13 and HXT15 (two polyol transporters) has been linked to growth on non-fermentable carbon sources [ 42 ].…”

Intracellular kynurenine promotes acetaldehyde accumulation, further inducing the apoptosis in soil beneficial fungi Trichoderma guizhouenseNJAU4742 under acid stress

“…As transporters of essential energy substances, hexose transporters have attracted much attention for their functional properties. Predecessors often studied their transport efficiency, but this study mainly explored their influence on the acid resistance of organisms, which further enriched their functional research (Nadai et al, 2021). Moreover, the genes about the glycolytic pathway in the transcriptome data were screened out, including 10 genes with fold change >2 (Figure S1).…”

Screening low-methanol and high-aroma produced yeasts for cider fermentation by transcriptive characterization

“…The HXT1 gene encodes carriers for hexose transport and plays as the sugar transporter during yeast growth, specialized for glucose and fructose (Munoz-Miranda et al, 2022). Strains in the absence of HXT1 genes could not grow on glucose or fructose and have no glycolytic flux (Nadai et al, 2021). HXT1 was activated in strains WFC-PK-045, WFC-PB-054, and WFC-SC-071 and exhibited lower expression levels at the end of fermentation.…”