Analysis of C. burnetii ATP pool during incubation in CCM. (A) C. burnetii ATP pools were compared following incubation in CCM (⧫), CSB (▾), or P-25 buffer (▪) for 2, 6, and 24 h. Data are expressed as the percentage of the total ATP pool of the inoculum (time zero). *, statistically significant differences (P < 0.05) between CCM and P-25 buffer; #, statistically significant differences (P < 0.05) between P-25 buffer and CSB. (B) The stability of the C. burnetii ATP pool during incubation in CCM supplemented with an efficiently oxidized carbon source was assessed. ATP was measured following a 3-h incubation in CCM or in CCM supplemented with 5 mM glutamate (glu), succinate (suc), or pyruvate (pyr). Asterisks indicate statistically significant differences between the inoculum and indicated sample. The broken line represents the ATP level of the inoculum normalized to 100%.