Figure 4. Growth of the mmpL3 cKD mutant and its parental strain TB38 in THP-1-derived macrophages.

Infection was performed at an MOI of 1:20 (bacteria/macrophage). The results are expressed as CFU/well. ATc (200 ng/ml) was added to the cell culture medium, when appropriate. Two separate infections were performed in duplicate. Triangles: mmpL3 mutant plus ATc; circles: parental strain TB38 plus ATc; squares: mmpL3 mutant with no ATc. While colonies were detectable until 4 days after infection starting from day 5 no colonies were detected from cell cultures infected with the mutant strain and treated with ATc (detection limit 20 cfu/well).