SLC11A1 and infection: In natural resistance-associated macrophage protein 1 (Nramp1)-negative J774.1 murine macrophages, significantly higher bacterial counts were observed for the mutant strains 4/74ΔzntA and 4/74ΔzntA/zitB compared to the WT at 4 h post-infection although the fold net replication was similar between all the strains.