Fig 6.
Independent and simultaneous induction of the lac promoter and tetracycline-inducible promoter (Ptet) within the same gonococcal cell. We constructed a strain (MR558) that expresses lacZ under the control of the lac promoter at the lctP-aspC site and traWSS::′phoA under the control of Ptet at the iga-trpB site. We then measured alkaline phosphatase activity and β-galactosidase activity in the presence or absence of 0.5 mM IPTG and/or 2 ng/ml ATc. Alkaline phosphatase activity and β-galactosidase activity were normalized to mg protein. The mean ± standard deviation of three independent experiments is shown.