Figure 3
Loss of Qdr amino acid exporters in the Ethanol Red strain prevents a lactic acid increase during growth on molasses. (A) Wild-type (black), qdr3Δ (orange), and qdr1Δ qdr2Δ qdr3Δ (blue) Ethanol Red cells were grown on nonsterile molasses-based medium and weight loss was monitored along time. Arrow show the end of each fermentation and the sampling timepoint. (B) Ethanol concentration in the medium at the end of each fermentation. (C) Lactic acid concentration at the end of each fermentation. The dotted line corresponds to the lactic acid detected in the medium before inoculation with yeast. (D) Concentrations of lactic acid expressed as percentages of that observed in supernatants of the wild-type cultures. Bars represent averages of three independent experiments ± standard deviation (SD). * indicates a statistically significant difference as determined with the unpaired t test. ** P < 0.0021; ns: not significant, P > 0.05.
