Figure 7.

Enzymatically active NadB is required for normal CCV formation and C. burnetii growth inside cells. Representative micrographs (three independent experiments) of HeLa cells (A) and THP-1 cells (B) infected with C. burnetii strains for 3 days are shown. The cells were fixed and stained with anti-Coxiella (red), anti-LAMP1 (green), and DAPI (blue), and white asterisks indicate representative CCVs. Note that WT C. burnetii NMII and the complemented nadB mutant produced large CCVs containing numerous bacteria, whereas both the nadB mutant and the R275L complemented nadB mutant displayed smaller CCVs containing very few bacteria. The scale bars represent 10 μm.