Table 1.
Hydrogen-producing and oxidizing activities of cell suspensions and cellular fractions of S. multivorans and S. cavolei cultivated with pyruvate or with pyruvate/fumarate
| Cellular fraction | Hydrogenase activity (nkat mg-1) | |||||
|---|---|---|---|---|---|---|
| S. multivorans | S. cavolei | |||||
| MV → H2 | H2 → BV | H2 → MV | MV → H2 | H2 → BV | H2 → MV | |
| Cell suspensions | ||||||
| Pyr | <0.01 | 4.1 ± 0.5 | 0.7 ± 0.3 | <0.01 | 5.5 ± 0.6 | 1.4 ± 0.3 |
| Membrane fractions | ||||||
| Pyr | 12.3 ± 2.4 | 23.5 ± 2.1 | n.d. | 20.6 ± 3.7 | 10.1 ± 0.5 | n.d. |
| Pyr + Fum | 5.7 ± 1.5 | 36.6 ± 3.3 | n.d. | 10.1 ± 2.4 | 13.5 ± 1.6 | n.d. |
| Soluble fractions | ||||||
| Pyr | <0.01 | n.d. | n.d. | <0.01 | n.d. | n.d. |
| Pyr + Fum | <0.01 | 2.3 ± 0.3 | n.d. | <0.01 | 1.9 ± 0.3 | n.d. |
MV → H2 indicates H2 formation activity, H2 → BV/MV indicates H2 oxidation
Data are derived from three independent biological replicates and show means ± standard deviation
MV methyl viologen, BV benzyl viologen, Pyr pyruvate, Fum fumarate, n.d. not determined