Activation of MAPK signaling observed in macrophages infected with the sodBC mutant is dependent on NADPH oxidase-generated ROS. Quantitation of phosphorylated (Phospho) p38, JNK, and ERK at 30 min post-infection. ELISA was performed using wild type or phox−/− BMDMs infected with F. tularensis (Ft) LVS, sodBC mutant, or the transcomplemented (sodBC+psodC) strain. The data are representative of two independent experiments (n = 3 replicates) and were analyzed using one-way ANOVA, and p values were calculated.