Table 2.
ToxR/S and TcpP/H activation of toxT
| Strain | β-Galactosidase activity (Miller units) after growth in arabinose
|
||
|---|---|---|---|
| 0% | 0.002% | 0.02% | |
| ΔtcpP ΔtoxR toxT::lacZ | 21.47 ± 3.95 | 26.16 ± 2.53 | 25.60 ± 2.15 |
| ΔtcpP ΔtoxR toxT::lacZ (pVJ21) | 39.59 ± 4.87 | 55.11 ± 3.52 | 53.09 ± 2.53 |
| ΔtcpP ΔtoxR toxT::lacZ (PBAD-PH) | 22.66 ± 6.95 | 20.32 ± 0.76 | 368.22 ± 31.38 |
| ΔtcpP ΔtoxR toxT::lacZ (pBAD-PH, pVJ21) | 36.94 ± 2.56 | 770.66 ± 50.52 | 2,346.27 ± 429.23 |
β-Galactosidase activities are shown for a ΔtcpP ΔtoxR double mutant V. cholerae strain carrying a toxT::lacZ reporter construct in the chromosome with plasmids expressing the toxR and toxS genes constitutively (pVJ21) and/or the tcpP and tcpH genes from an arabinose-inducible promoter (pBAD-PH). Results are mean ± SD.