Skip to main content

Table 1 Growth characteristics of anaerobically evolved hxt0-strains expressing proton symporters and a hxt0 strain expressing HXT5 in either glucose- or fructose-limited anaerobic steady state chemostat cultures at a dilution rate of 0.07 h−1

From: Engineering proton-coupled hexose uptake in Saccharomyces cerevisiae for improved ethanol yield

Strain IMZ763 IMS1058 IMS1061 IMZ763 IMS1059 IMS1060
Hexose transporter HXT5 MAL11 KmHGT1 HXT5 KlFRT1 SeFSY1
Carbon source Glucose Glucose Glucose Fructose Fructose Fructose
µmax (h−1a 0.22 ± 0.00 0.21 ± 0.01 0.13 ± 0.00 0.23 ± 0.00 0.16 ± 0.00 0.11 ± 0.00
Biomass yield (gx gs−1) 0.084 ± 0.001 0.044 ± 0.000 0.047 ± 0.000 0.088 ± 0.003 0.047 ± 0.000 0.048 ± 0.001
Ethanol yield (mol mols−1) 1.51 ± 0.01 1.77 ± 0.01 1.73 ± 0.00 1.58 ± 0.02 1.79 ± 0.01 1.75 ± 0.02
qs (mmol gx−1 h−1) -4.69 ± 0.06 -8.87 ± 0.15 -8.38 ± 0.16 -4.46 ± 0.13 -8.38 ± 0.02 -8.11 ± 0.36
qethanol (mmol gx−1 h−1) 7.08 ± 0.05 15.70 ± 0.13 14.53 ± 0.28 7.03 ± 0.10 14.98 ± 0.12 14.16 ± 0.50
qglycerol (mmol gx−1 h−1) 0.59 ± 0.01 0.68 ± 0.00 0.59 ± 0.00 0.53 ± 0.00 0.58 ± 0.02 0.55 ± 0.03
qCO2 (mmol gx−1 h−1) 7.85 ± 0.06 15.91 ± 0.09 15.36 ± 0.33 7.32 ± 0.12 15.36 ± 0.05 14.88 ± 0.39
Residual sugar (g L−1) 0.16 ± 0.03 2.87 + 0.16 0.11 ± 0.00 0.93 ± 0.05 1.02 ± 0.02 0.12 ± 0.02
Carbon recovery (%) b 96.4 ± 0.1 99.0 ± 1.1 98.4 ± 0.1 98.3 ± 1.4 99.8 ± 0.0 98.7 ± 1.2
Actual dilution rate (h−1) 0.071 ± 0.002 0.071 ± 0.001 0.071 ± 0.001 0.071 ± 0.004 0.071 ± 0.000 0.070 ± 0.001
  1. aThe maximum specific growth rate (µmax) was determined based on measurements of the CO2 concentration in the reactor off-gas during the preceding batch phase
  2. Biomass-specific production and consumption rates are depicted as qmetabolite
  3. bThe carbon recovery represents the percentage of the carbon entering the reactor system via the medium that could be traced back in biomass, products and residual substrate
  4. The data represent average values and mean deviations obtained from duplicate experiments