TABLE 2.
Fermentation of glucose with different concentrations of formatea
| Amt of added formate (mM) | Fermentation with the following substrates and products (mM):
|
C recovery (%) | O/Rb | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Used
|
Formed
|
||||||||
| Glucose | Formate | CO2 | Succinate | Acetate | Lactate | CO2 | |||
| 0 | 14.3 | 0.0 | 5.8 | 11.6 | 10.0 | 7.0 | 0.0 | 95 | 1.00 |
| 4.8 | 23.2 | 4.8 | 9.3 | 18.6 | 23.1 | 13.0 | 2.8 | 106 | 1.03 |
| 48 | 25.1 | 27.2 | 2.2 | 4.4 | 70.3 | 1.6 | 13.6 | 98 | 1.00 |
a
Cultures, inoculated with an unwashed inoculum, were incubated in B1C medium with 28 mM glucose without formate, except as indicated in the table, for 48 h. After gas analysis (23), cultures were acidified and analyzed by high-performance liquid chromatography (9, 18). The amounts of the acid products in the medium immediately after inoculation were similarly determined and were subtracted from the final values. The following equations were used to estimate CO2 utilization and production: 3 C6H12O6 + 4 HCO2H → 10 CH3COOH + 2 CO2 + 2 H2O; 3 C6H12O6 + 2 CO2 → 4 HOOC(CH2)2COOH + 2 CH3COOH + 2 H2O; and C6H12O6 → 2 CH3CHOHCOOH.
b
O/R, oxidation equivalents/reduction equivalents.