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

Hexose transporter

HXT5

MAL11

KmHGT1

HXT5

KlFRT1

SeFSY1

Carbon source

Glucose

Glucose

Glucose

Fructose

Fructose

Fructose

µ_max (h⁻¹) ^a

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 (g_x g_s⁻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 mol_s⁻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

q_s (mmol g_x⁻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

q_ethanol (mmol g_x⁻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

q_glycerol (mmol g_x⁻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

q_CO2 (mmol g_x⁻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