Fig. 3

Effect of low glucose–xylose mix on induction of xylose utilization in different S. cerevisiae strains. The ZNF1-OE strain overexpressing ZNF1 gene was investigated during culture in YPX containing 2% xylose (w/v) and low glucose at concentration of 0.05%, 0.04%, 0.03%, 0.02%, 0.01% (w/v) or without glucose expressed in term of cell dry weight (g/L) (A), Cell survival was analyzed using CFU/ml method (B), Glucose concentration (g/L) (C), Xylose concentration (g/L) (D), Phenotypic analysis on increased concentration of xylose (E). The wild-type BY4742, the znf1∆, the bud21∆, the rescued strain (znf1∆ + pLJ529-ZNF1) the overexpression ZNF1 (BY4742 + pLJ529-ZNF1 and ZNF1-OE), and the engineered bud21∆ + pLJ529-ZNF1 of S. cerevisiae strains were observed on YPX agar plates contained 0.05% glucose mixed with different concentration of xylose at 2 or 10% (w/v). Ten-fold serial dilutions of cells were spotted on plates and incubated at 30 °C for 2–5 days. Error bars indicated standard deviations calculated from at least two independent experiments performed in triplicate. Significance differences were determined by one-way ANOVA with Tukey HSD method (*, p < 0.05; **, p < 0.01)