Cysteine Protease

Cysteine proteases, also known as thiol proteases, are a class of hydrolase enzymes that catalyze the hydrolysis of peptide bonds in proteins using a nucleophilic cysteine residue at their active site. They are found across all domains of life and play essential roles in physiological processes such as protein turnover, cell signaling, apoptosis (programmed cell death), immune responses, and development. Cysteine protease activity is tightly regulated by endogenous inhibitors called *cystatins*, which prevent uncontrolled protein degradation. Dysregulation can lead to pathological conditions including cancer progression, neurodegeneration, osteoporosis, cardiovascular disease, parasitic infections, etc. Due to their central role in disease mechanisms—including parasite pathogenesis—they are attractive targets for drug discovery efforts against infectious diseases like malaria as well as inflammatory disorders and cancer therapy. Several small-molecule inhibitors targeting specific family members are under investigation or clinical use.

Other names

Thiol Protease

Inhibition of cysteine protease activity