TABLE 1.
Nitrogen cycle gene probes
| Transformation | Gene(s)a | Protein | Reference(s) |
|---|---|---|---|
| N2 fixation | nifHDK | Nitrogenase | 117 |
| Nitrite assimilation | nir | Nitrite reductase | 102 |
| Nitrate assimilation | narB, nasA | Assimilatory nitrate reductase | 1 |
| Ammonium assimilation | glnA | Glutamine synthetase | 54 |
| Nitrate respiration and denitrification | nirS | Nitrate reductase | 8, 18, 87 |
| nirK | Nitrite reductase | ||
| norB | Nitric oxide reductase | ||
| nosZ | Nitrous oxide reductase | ||
| Organic N metabolism | ure | Urease | 25 |
| Ammonium oxidation/nitrification | amo | Ammonia monooxygenase | 2, 83 |
| Nitrogen regulation (cyanobacteria) | ntcA | Nitrogen regulatory protein | 58 |
a
Nitrogen cycle genes for which probes or PCR primers have been designed.