Table 2.
Physiological characteristics of N. europae a wild type and fur:kanP mutant grown under Fe-replete (10 μM) and Fe-limited (0.2 μM) conditions*
| Physiological Characteristic | Wild type | fur:kanP mutant | ||
|---|---|---|---|---|
| Fe-replete | Fe-limited | Fe-replete | Fe-limited | |
|
Heme c content in cell's soluble fraction |
||||
| Heme c (nmol/ml culture) | 0.85 ± 0.02 | 0.38 ± 0.05 | 0.48 ± 0.02 | 0.21 ± 0.04 |
| Heme c (nmol/mg protein) | 7.77 ± 0.23 | 4.04 ± 0.53 | 5.67 ± 0.31 | 5.04 ± 0.91 |
| Whole Cell Fe content | ||||
| Fe (nmol/ml culture) | 1.36 ± 0.15 | 0.15 ± 0.01 | 2.04 ± 0.09 | 0.11 ± 0.01 |
| Fe (nmol/mg protein) | 90.4 ± 6.0 | 26.4 ± 2.0 | 136.2 ± 14.0 | 24.9 ± 3.0 |
| Cellular Fe concentration (mM) | 8.27 ± 0.94 | 1.99 ± 0.13 | 12.4 ± 0.6 | 1.98 ± 0.18 |
| Whole cell enzyme-catalyzed activity | ||||
| NH4+-dependent O2 consumption (nmol/(min × OD600 nm) | 94.5 ± 4.1 | 38.1 ± 6.0 | 88.2 ± 2.5 | 21.7 ± 0.6 |
| NH4+-dependent O2 consumption (nmol/(min × mg protein) | 1500 ± 63 | 779 ± 17 | 1446 ± 40 | 680 ± 18 |
| NH2OH-dependent O2 consumption (nmol/(min × OD600 nm) | 25.9 ± 0.2 | 10.9 ± 2.4 | 25.7 ± 4.8 | 4.6 ± 0.2 |
| NH2OH-dependent O2 consumption (nmol/(min × mg protein) | 412 ± 3.0 | 222 ± 5.0 | 421 ± 2.0 | 146 ± 6.0 |
*Data are means of triplicates, with variation less than 10%. The experiment was repeated several times and produced similar results. Data are means ± S.D.