Protease subunit of a proteasome-like degradation complex. HslU recognizes protein substrates and unfolds these before guiding them to HslV for hydrolysis. HslV is not believed to degrade folded proteins (By similarity). The HslVU protease complex functions in mitochondrial DNA replication by regulating DNA helicase PIF2 protein levels. ATP-dependent cleavage of peptide bonds with broad specificity. A double ring-shaped homohexamer of HslV is capped on each side by a ring-shaped HslU homohexamer. The assembly of the HslU/HslV complex (HslVU) is dependent on binding of ATP (By similarity). Associated with kinetoplast DNA (kDNA). Belongs to the peptidase T1B family. HslV subfamily.