FIG. 3.
Effect of CCM nutrient supplements on C. burnetii metabolic fitness. The relative impact of CCM nutrient supplements on C. burnetii metabolic fitness was determined by incubating organisms in CSB supplemented with neopeptone (neopep), FBS, or RPMI medium. Bacteria were preincubated in the respective medium formulations for 24 h and then labeled with [35S]Cys-Met in labeling buffer (pH 4.5) for 3 h. De novo protein synthesis by C. burnetii was measured by quantification of radiolabel incorporation by scintillation counting. Results are expressed as the relative increase in radiolabel incorporation compared to the incorporation of bacteria labeled in labeling buffer (pH 7.0) (negative control). Asterisks indicate statistically significant (P < 0.05) differences compared to CSB. The broken line represents the level of radiolabel incorporation in CCM (pH 7.0) normalized to 1.