Table 5.
Regulation of the promoter of bcam0192 by CepR2, CepS, and OHLa.
| Plasmid | Fragment | Genotype | OHL (uM) | β-Galacto- sidase | Normalized Valueb |
|---|---|---|---|---|---|
| pGR136 | −400 – +127 | WT | 0 | 32 ± 3 | (1) |
| WT | 1 | 367± 30 | 11.5 | ||
| GR141 (cepR2-) | 0 | 376 ± 31 | 11.8 | ||
| GR141 (cepR2-) | 1 | 368 ± 25 | 1.0 | ||
| GR145 (cepS-) | 0 | 3 ± 1 | 0.1 | ||
| GR145 (cepS-) | 1 | 4 ± 2 | 0.01 | ||
| pGR137 | −324 – +127 | WT | 0 | 78 ± 10 | (1) |
| WT | 1 | 357 ± 15 | 4.8 | ||
| GR141 (cepR2-) | 0 | 356 ± 23 | 4.6 | ||
| GR141 (cepR2-) | 1 | 374 ± 34 | 1.0 | ||
| GR145 (cepS-) | 0 | 7 ± 3 | 0.9 | ||
| GR145 (cepS-) | 1 | 5 ± 2 | 0.01 | ||
| pGR138 | −268 – +127 | WT | 0 | 217 ± 23 | (1) |
| WT | 1 | 263 ± 15 | 1.2 | ||
| GR141 (cepR2-) | 0 | 374 ± 18 | 1.7 | ||
| GR141 (cepR2-) | 1 | 382 ± 23 | 1.7 | ||
| GR145 (cepS-) | 0 | 4 ± 2 | 0.02 | ||
| GR145 (cepS-) | 1 | 7 ± 3 | 0.03 | ||
| pGR139 | −202 – +127 | WT | 0 | 370 ± 21 | (1) |
| WT | 1 | 375 ± 23 | 1.0 | ||
| GR141 (cepR2-) | 0 | 364 ± 26 | 1.0 | ||
| GR141 (cepR2-) | 1 | 384 ± 43 | 1.0 | ||
| GR145 (cepS-) | 0 | 12.5 ± 4 | 0.03 | ||
| GR145 (cepS-) | 1 | 18.7 ± 9 | 0.05 | ||
| pGR140 | −114 – +127 | WT | 0 | 5 ± 7 | (1) |
| WT | 1 | 4 ± 9 | 0.8 | ||
| GR141 (cepR2-) | 0 | 8 ± 6 | 1.6 | ||
| GR141 (cepR2-) | 1 | 5 ± 3 | 1.0 | ||
| GR145 (cepS-) | 0 | 3 ± 2 | 0.7 | ||
| GR145 (cepS-) | 1 | 3 ± 1 | 0.7 | ||
| pGR243 | −400 – -46 | WT | 0 | 75 ± 14 | (1) |
| WT | 1 | 332 ± 32 | 4.4 | ||
| GR141 (cepR2-) | 0 | 392 ± 32 | 5.2 | ||
| GR141 (cepR2-) | 1 | 421 ± 28 | 5.6 | ||
| GR145 (cepS-) | 0 | 2.4 ± 1.2 | 0.03 | ||
| GR145 (cepS-) | 1 | 5.6 ± 1.2 | 0.07 |
a
Derivatives of strain K56-I2 containing the indicated cepR2 or cepS mutations and the indicated plasmids were cultured at 37°C in LB supplemented with 300 μg ml−1 tetracycline to an optical density of approximately 0.4 in the presence or absence of 1 μM OHL, and assayed for β-galactosidase activity. Data were obtained from a single representative experiment using three independent isolates of each strain, each assayed once. Mean value and standard deviations are indicated.
b
β-galactosidase activity is normalized to that of the wild type strain carrying the indicated plasmid and cultured in the absence of OHL.