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Table 3 Specific growth rate (μ), yields (Y) of biomass, ethanol and glycerol on glucose and stoichiometric relationships between glycerol production and biomass formation in anaerobic bioreactor batch cultures of S. cerevisiae strains carrying different genetic modifications

From: Optimizing anaerobic growth rate and fermentation kinetics in Saccharomyces cerevisiae strains expressing Calvin-cycle enzymes for improved ethanol yield

Strain IME324 IMX773 IMX774 IMX949 IMX1443
Relevant genotype GPD1 GPD2 GPD1 GPD2 pYEN1-prk
cbbm
GPD1 GPD2 pDAN1-prk
cbbm
GPD1 gpd2Δ pDAN1-prk
cbbm
GPD1 gpd2Δ pDAN1-prk
cbbm
non-ox PPP↑
μ (h−1) 0.32 ± 0.02 0.28 ± 0.01* 0.22 ± 0.02** 0.22 ± 0.01** 0.30 ± 0.01
Y biomass/glucose (g g−1) 0.090 ± 0.002 0.089 ± 0.001 0.087 ± 0.004 0.095 ± 0.004 0.099 ± 0.005*
Y ethanol/glucose (g g−1) 0.364 ± 0.015 0.385 ± 0.002 0.400 ± 0.006** 0.411 ± 0.002** 0.419 ± 0.001**
Y glycerol/glucose (g g−1) 0.101 ± 0.003 0.098 ± 0.000 0.070 ± 0.005** 0.038 ± 0.001** 0.013 ± 0.000**
Glycerol produced/biomass [mmol (g biomass)−1] 12.239 ± 0.095 11.880 ± 0.008* 7.622 ± 0.409** 4.314 ± 0.245** 1.507 ± 0.119**
  1. Cultures were grown on synthetic medium containing 20 g L−1 glucose (pH 5). Specific growth rates and stoichiometries were calculated from multiple sample points in the mid-exponential growth phase. Values represent averages ± mean deviations of measurements on independent cultures. Cultures of IME324, IMX949, and IMX1443 were performed in triplicate. Cultures of IMX774 were performed in quadruplicate and cultures of IMX773 were performed in duplicate. * (p < 0.05) and ** (p < 0.01) denote statistical significance of value differences between IME324 and each engineered strain in Student’s t tests. Degree of reduction balances constructed over the exponential growth phase yielded electron recoveries between 96 and 101%