FIG 5.

Influence of NTPases I and II on firefly and Gaussia luciferase reporter lines. IFN-γ-inducible tandem GAS element-driven FLUC reporter lines were infected with different MOIs for 3 h and subsequently stimulated with 100 U of IFN-γ/ml for 18 h. NTPase I and double-knockout mutants were significantly less capable at suppressing FLUC activity in both RAW264.7 macrophages (A) and HeLa cells (B) than the wild-type RH strain. Asterisks (*) indicate a P value of <0.05 between the wild type and NTPase I and double-knockout mutants. (C) The addition of ATP during cell lysis or the absence of DTT in the lysis buffer partially reversed the interference with the firefly luciferase reporter. Asterisks (*) indicate a P value of <0.05 between cell lysis with or without DTT. (D) An IFN-γ-inducible tandem GAS element-driven ATP-independent GLUC RAW264.7 macrophage reporter line showed no NTPase-dependent effect. The data shown are averages ± SEM of at least three independent experiments, each performed with three technical replicates (A, C, and D), and averages ± SD of two independent experiments with three technical replicates (B).