TABLE 2.
Effect of ptsP mutation on transcription of nifHa
| Strain | Genotype | β-Galactosidase sp act (Miller units) at:
|
||
|---|---|---|---|---|
| 0 h | 4 h
|
|||
| Without ammonium | With ammonium | |||
| MV101 | ptsP (wild type) | 135.5 ± 11.2 | 1,392.9 ± 125 | 82.4 ± 1 |
| DS989 | ptsP | 154.4 ± 51.8 | 1,219.0 ± 111 | 79.2 ± 7 |
a
Cells were grown for 20 h on BS and 10 mM urea, washed with Burk’s buffer, and incubated for 4 h on Burk’s medium supplemented with 11 mM glucose with or without 10 mM ammonium chloride. Values are the means of three determinations.