FIGURE 1.

The Mycobacterium tuberculosis (Mtb) RpoB H526D mutant strain exhibits slow growth rate and altered colony morphology. (A) Growth kinetics of Mtb strains in supplemented Middlebrook 7H9 broth. ^∗∗p < 0.01, ^∗∗∗p < 0.001, ^∗∗∗∗p < 0.0001. (B) Mtb cultures were grown on Middlebrook 7H10 agar and colonies were photographed 32 days post-inoculation. Colonies of the RpoB H526D mutant are smaller, more translucent, and less regular than those of the parental strain.