TABLE 3.
Culture | Substrate | YXFermS (g [dry wt] · mol−1) | qXFermSmaxa (mol-S · [g (dry wt) · day]−1) | Acetateb (mM) | H2b (Pa) | ΔG′c (kJ · mol-S−1) | YXFermΔGd (g [dry wt] · 70 kJ−1) |
---|---|---|---|---|---|---|---|
Isophthalate | Isophthalate | 4.7 | 0.019 | 1.6 | 3.5 | −92.4 | 3.6 |
Benzoate | 7.8 | 0.017 | 2.5 | 6.0 | −56.0 | 9.7 | |
Phthalate | Phthalate | 4.3 | 0.020 | 4.0 | 4.0 | −88.5 | 3.4 |
Benzoate | 9.0 | 0.024 | 10.0 | 6.0 | −45.2 | 13.9 | |
Terephthalate | Terephthalate | 4.0 | 0.023 | 1.3 | 3.0 | −95.4 | 3.0 |
Benzoate | 8.4 | 0.021 | 2.5 | 4.0 | −59.1 | 10.0 |
The maximum specific conversion rate was calculated according as follows: qXFermSmax = μSmax · YXFermS−1.
The acetate and hydrogen concentrations represent average concentrations, as measured during exponential growth of the cultures.
Values for the actual Gibbs free-energy change for fermentation of the phthalate isomers (reaction 1, Table 1) and benzoate (reaction 2, Table 1), calculated with a concentration of 4 mM for the phthalate isomers and benzoate and a bicarbonate concentration of 40 mM.
Measured biomass yields (see Table 2) normalized to an energy quantum of 70 kJ · (mol-S)−1.