Table 1.

β-Galactosidase activity ofapeE::lacZ fusions in limiting and excess phosphate

StrainGenotypeβ-Galactosidase activitya (Miller units) in:
2 mM phosphate0.1 mM phosphate
CAC13ΔleuBCD485 apeE14::MudI-17341.5210
CAC47ΔleuBCD485 apeE14::MudI-1734apeR1225241
CAC49ΔleuBCD485 apeE14::MudI-1734 ΔphoB1::cat1.81.6
CAC50ΔleuBCD485 apeE14::MudI-1734 ΔphoB1::cat apeR11.92.0
CAC39ΔleuBCD485 apeE14::MudI-1734katF::bla1.0272
CAC97ΔleuBCD485 apeE14::MudI-1734phoP53::Tn10dTet0.8134
CAC99ΔleuBCD485 apeE14::MudI-1734ntrA209::Tn100.8149
  • a Strains were grown overnight in morpholine propanesulfonic acid minimal medium with either 2 mM K2HPO4 and 0.06% glucose or 0.1 mM K2HPO4 and 0.4% glucose (8). The β-galactosidase activity was assayed as described by Miller (10). Each assay was performed in triplicate, and all strains were assayed at least twice.