Fig. 8

Transcriptional analysis of CtpB under stress conditions. Relative transcription of ctpB from cultures separately supplemented with different concentrations of heavy-metal cations (Cd²⁺, Co²⁺, Cu²⁺, Fe²⁺, Mn²⁺, Ni²⁺, Pb²⁺, and Zn²⁺), hypoxia, and 1 mM of different redox stress agents (H₂O₂, tert butyl hydroperoxide, KCN, and sodium nitroprusside). sigA was used as the normalizer gene. The data were plotted as the average values ± SEM from three independent experiments. The differences (*P < 0.05) were obtained by comparing the values in the presence and absence of the stress conditions