Table 1.
SigR-binding activity and diamide sensitivity of RsrA variants
| RsrA | BLa | IDIF50 (µM)b | Relative IDIF50c | RsrA | BL | IDIF50 (µM) | Relative IDIF50 |
|---|---|---|---|---|---|---|---|
| WT | 0.8 ± 0.1 | 39.5 ± 3.5 | 1.0 | C41A | 6.7 | ND | ND |
| K33A | 1.1 ± 0.1 | 79.6 ± 7.2 | 2.0 | S42A | 0.7 ± 0.1 | 110.3 ± 21.9 | 2.8 |
| F34A | 2.8 ± 1.9 | 49.9 ± 6.8 | 1.3 | P43A | 0.4 ± 0.3 | 45.5 ± 12.3 | 1.2 |
| E35A | 0.9 ± 0.5 | 54.8 ± 38.3 | 1.4 | C44A | 7.1 | ND | ND |
| H36A | 0.6 ± 0.2 | 103.8 ± 14.0 | 2.6 | L45A | 0.7 ± 0.3 | 303.3 ± 86.7 | 7.7 |
| H37A | 5.7 | ND | ND | E46A | 0.8 ± 0.3 | 158.6 ± 34.1 | 4.0 |
| F38A | 8.0 ± 3.1 | ND | ND | K47A | 0.7 ± 0.4 | 38.5 ± 16.8 | 1.0 |
| E39A | 0.6 ± 0.2 | 128.3 ± 42.4 | 3.2 | S-RsrA | 1.4 ± 0.5 | 9.1 ± 0.6 | 0.2 |
| E40A | 0.9 ± 0.3 | 191.4 ± 146.6 | 4.8 |
aThe basal-level (BL) expression of sigRp2 was normalized in each sample to the level of constitutive sigRp1 expression in the absence of diamide. For each sample, the value was presented as an average ± standard deviation from more than three independent experiments except for H37A, H41A and H44A.
bThe diamide concentration in micromolar (induction dose; ID) needed to induce sigRp2 to the level corresponding to half-maximum induction fold (IF50). Each value represents an average ± standard deviation from more than three independent experiments. ND, not-determined.
cRelative IDIF50 is in comparison with the wild-type value set as 1.0.