TABLE 5.
Hydrogenase activity in E. coli HYD723 expressing pBADE1 or derivative plasmids carrying mutations in histidine residues of HupE
| Plasmid | Hydrogenase activitya obtained with: |
|
|---|---|---|
| 200 μM arabinose | No inducer | |
| pBADE1 | 1,700 ± 420 | 20 ± 20 |
| pBAD18-Kan | 100 ± 80 | 40 ± 30 |
| pBADE1.H22I | 2,450 ± 670 | 70 ± 60 |
| pBADE1.H26I | 1,390 ± 200 | 100 ± 30 |
| pBADE1.H22I/H26I | 720 ± 240 | 40 ± 10 |
| pBADE1.H36I | 70 ± 20 | 210 ± 10 |
| pBADE1.H43I | 260 ± 130 | 210 ± 100 |
| pBADE1.H126I | 610 ± 190 | 30 ± 30 |
| pBADE1.H128I | 1,960 ± 510 | 60 ± 40 |
| pBADE1.H130I | 190 ± 100 | 140 ± 40 |
| pBADE1.H155I | 1,190 ± 60 | 40 ± 10 |
a
Hydrogenase activities (expressed in nmol H2 h−1 mg prot−1) in anaerobic cells were measured, using oxygen as an electron acceptor. Values are means of results from three independent assays ± SE.