Table 2.
Reactions catalyzed by cell suspensions of M. barkeri strains
| Reaction | M. barkeri (nmol min−1 mg−1) | M. barkeri Ech1 (nmol min−1 mg−1) |
|---|---|---|
| 4 CH3OH → 3 CH4 + CO2 + 2 H2O* | 174 (±23) | 176 (±15) |
| CH3OH + H2 → CH4 + H2O† | 440 (±125) | 520 (±160) |
| CH2O + 2 H2 → CH4 + H2O‡ | 97 (±29) | 113 (±57) |
| CO2 + 4 H2 → CH4 + 2 H2O§ | 78 (±9) | ≪1 |
| CO + H2O → CO2 + H2¶ | 26 (±7) | 3 (±1) |
Assays contained 125 mM methanol and cell suspensions at protein concentrations of 5–20 mg/ml. CH4 production was assayed.
The gas phase was 100% H2. Assays contained 125 mM methanol and cell suspensions at protein concentrations of 5–20 mg/ml. CH4 production was assayed.
The gas phase was 100% H2. Assays contained 5 mM formaldehyde and suspended cells at a protein concentration of 6 mg/ml. CH4 production was assayed.
The gas phase was 80% H2/20% CO2. The assays contained cell suspensions at a protein concentration of 13 mg/ml. CH4 production was assayed.
To prevent methanogenesis, cultures were incubated with 20 mM bromoethanesulfonic acid (BES) for 1 h before harvesting. Cell suspensions also contained 20 mM BES. The gas phase was 10% CO/90% N2. The assays contained cell suspensions at protein concentrations of 5–10 mg/ml. Consumption of CO and production H2 and CH4 was assayed.