RT-PCR of clp genes during hypoxia. RT-PCR of clp proteases during hypoxia. a, clpP1. b, clpP2. c, clpC. d, clpX. Induction of clpP1, clpP2, and clpC occurred by 5 days post-hypoxia in Mtb. clpP2 expression occurred at 7 days post-hypoxia treatment in Mtb:ΔRv2745c, whereas there was no induction of clpP1 and clpC throughout hypoxia treatment. clpX expression -fold change was <1 for all time points and strains throughout hypoxia.