Table 2.
Physiology data in chemostat cultures
| B36 | OE gsdA | OE gndA | OE maeA | |
|---|---|---|---|---|
| µexponential phase (h−1) | 0.21 ± 0.01 | 0.21 ± 0.02 | 0.21 ± 0.01 | 0.19 ± 0.01 |
| Cbiomass (gDCW/kg) | 5.66 ± 0.16 | 7.5 ± 0.36 | 6.46 ± 0.17 | 4.74 ± 0.29 |
| qCO2 (mmol/gDCW·h) | 1.33 ± 0.04 | 1.00 ± 0.03 | 1.1 ± 0.03 | 1.45 ± 0.09 |
| qO2 (mmol/gDCW·h) | 1.6 ± 0.18 | 1.19 ± 0.15 | 1.51 ± 0.11 | 1.79 ± 0.20 |
| RQ | 0.83 ± 0.09 | 0.81 ± 0.1 | 0.73 ± 0.06 | 0.81 ± 0.09 |
| qProtein (mg/gDCW·h) | 3.71 ± 0.41 | 2.27 ± 0.37 | 5.62 ± 1 | 4.94 ± 0.49 |
| qs (mmolmaltose /gDCW·h) | 0.39 ± 0.011 | 0.31 ± 0.009 | 0.35 ± 0.031 | 0.47 ± 0.011 |
| YGlaA/X (U/gDCW) | 23.84 ± 1.08 | 14.38 ± 0.82 | 38.88 ± 3.6 | 30.83 ± 0.1 |
| C-recovery | 99% | 110% | 104% | 91% |
Data for strain B36 and three Tet-on driven overexpression strains derived thereof are shown for chemostat cultures with maltose as growth-limiting substrate. Standard deviations ( ±) are given for mean values of duplicate independent steady state results which were measured in technical triplicates. OE gsdA: strain overexpressing gene gsdA; OE gndA: strain overexpressing gene gndA; OE maeA: strain overexpressing gene maeA. Cbiomass, biomass concentration (dry cell weight (DCW)); qCO2, specific carbon dioxide evolution rate; qO2, specific oxygen uptake rate; RQ, respiratory quotient calculated as the ratio of CO2 production and O2 consumption rates; qprotein, specific production rate of extracellular protein; qs, specific substrate consumption rate; YGlaA/X, yield of total glucoamylase activity on biomass; C-recovery, carbon recovery