TABLE 5.
Energetic efficiency of different metabolic modes for consumption of lactate, ethanol, acetate, and acetoin
| Mode of metabolism | No. of moles formed |
Key enzyme(s), pathway [references(s)] | ||
|---|---|---|---|---|
| NADH + H+ | ATP (GTP) | ATP equivalentsa | ||
| Ethanol-acetate | 2 | 0 | 1 | Membrane-bound dehydrogenase (56, 57) |
| Ethanol-CO2 | 6 | −1c | 2 | Acetyl-CoA synthetase, TCA (22) |
| Acetate-CO2c | 4 | −1c | 1 | Acetyl-CoA synthetase, TCA (22) |
| Lactate-acetate | 2 | 0 | 1 | Pyruvate decarboxylase (73) |
| Lactate-CO2 | 6 | 1 | 4 | Pyruvate dehydrogenase, TCA (22) |
| Lactate-acetoin | 1 | 0 | 0.5 | Acetolactate synthase (21, 40) |
| Acetoinb-CO2 | 10 | 0 | 5 | Acetoin dehydrogenase and acetyl-CoA synthetase, TCA (21, 40) |