Figure 5. A catalytically inactive ClpP allele inhibit Mtb growth in vitro and during infection.

(A) Growth curves for Mtb overexpressing wild type ClpP1 or ClpP1 S98A via an ATc-inducible expression vector. Data are represented as mean OD₆₀₀ +/− standard deviation. Dashed lines represent assumed growth rates until first measured growth point. (B) Growth of Mtb containing a doxycycline-inducible plasmid expressing the mutant allele ClpP1 S98A in lungs of C57BL/6 mice 30 days post aerosol infection. Mice were infected via aerosol with a 3∶1 mixture of mutant and wild type bacteria. Mice were fed either with chow containing (dark squares, N = 5 mice) or lacking (gray triangles, N = 5 mice) the inducer doxycycline. As a control, wild type Mtb was co-infected, and representative CFU/organs for the control are represented (right). Each point represents calculated total CFU/organ for each mouse. Not all mice received enough wild type bacteria to quantitate.