TNF and infection: During infection, CopC I55D/F58D/L59D, complemented into the C. violaceum ΔcopC, also failed to block TNF-α-plus-CHX stimulation of the apoptotic program in HeLa cells, evident from the diminished cleavage of caspase-3, caspase-7, and PARP1 (Fig. 4G).