Cleaves peptides in various proteins in a process that requires ATP hydrolysis. Has a chymotrypsin-like activity. Plays a major role in the degradation of misfolded proteins (By similarity). Probably partially responsible for degradation of ECF sigma factor SigR prime. Hydrolysis of proteins to small peptides in the presence of ATP and magnesium. alpha-casein is the usual test substrate. In the absence of ATP, only oligopeptides shorter than five residues are hydrolyzed (such as succinyl-Leu-Tyr-|-NHMec, and Leu-Tyr-Leu-|-Tyr-Trp, in which cleavage of the -Tyr-|-Leu- and -Tyr-|-Trp bonds also occurs). Fourteen ClpP subunits assemble into 2 heptameric rings which stack back to back to give a disk-like structure with a central cavity, resembling the structure of eukaryotic proteasomes. Expressed from 2 promoters, 1 of which (clpP2) is positively regulated by the thio-oxidizing agent diamide, probably via SigR. Probably a clpP1-clpP2 operon. A double clpP1-clpP2 deletion increases the stability of ECF sigma factor SigR prime from 10 to 23 minutes. Belongs to the peptidase S14 family.