TABLE 2.
Activity of Mo-nitrogenase in the presence of a constitutively expressed AmtB
| Strain | Relevant genotype | Nitrogenase activitya
|
|
|---|---|---|---|
| +NH4+b | −NH4+c | ||
| B10S | Wild type | 3.0 ± 1.6 | 619 ± 80.5 |
| PHU332 | glnB | 0.7 ± 0.1 | 725 ± 13.0 |
| BSRUB13 | glnK | 1.9 ± 0.3 | 599 ± 20.7 |
| B10S(pBSRUB21-I) | PaphII::amtB | 0.8 ± 0.1 | 657 ± 55.5 |
| PHU332(pBSRUB21-I) | glnB PaphII::amtB | 1.2 ± 0.1 | 572 ± 20.1 |
| BSRUB13(pBSRUB21-I) | glnK PaphII::amtB | 70 ± 4.6 | 718 ± 13.0 |
a
Activities are given in nmol of ethylene produced/h/mg protein. Values are means of at least three independent experiments ± standard deviations.
b
Strains were cultivated in RCV medium plus 20 mM NH4+.
c
Strains were cultivated in RCV medium plus 9.5 mM serine.