Proteasome inhibitors function by binding to the active sites of the proteasome, thereby blocking its proteolytic activity. The proteasome contains multiple types of catalytic sites, including chymotrypsin-like, trypsin-like, and caspase-like sites, each responsible for cleaving specific peptide bonds. Inhibitors can target one or more of these catalytic sites, leading to a reduction in protein degradation and accumulation of polyubiquitinated proteins.
