There were no statistically significant differences between the uptake of mutants and WT by the Nramp1-negative J774.1 macrophages (Figure 3A) while CFU counts for 4/74ΔzntA and 4/74ΔzntA/zitB were significantly higher than those obtained for the WT isolate at 4 h post-infection (Figure 3C). This evidence concerns the gene SLC11A1 and infection.