Protozoal cysteine protease

Protozoal cysteine proteases are a major class of enzymes employed by parasites to facilitate infection, tissue invasion, immune evasion, protein degradation, autophagy, and cellular egress[1][2]. The most well-characterized families include clan CA cysteine proteases—particularly family C1 cathepsin-like enzymes—which are considered druggable targets in malaria (*Plasmodium* falcipain), Chagas disease (*Trypanosoma cruzi* cruzipain), leishmaniasis, and other protozoan infections. These proteases commonly hydrolyze host or parasite proteins and are involved in key biological processes, including hemoglobin degradation (in *Plasmodium*), cell penetration, and autophagy. Inhibiting these enzymes is a promising approach for chemotherapeutic and vaccine strategies. However, the term "protozoal cysteine-containing proteins" is not standard; the precise therapeutic target class is "protozoal cysteine protease"[1][2].

Other names

Cysteine peptidaseCathepsin-like proteaseClan CA cysteine proteaseCathepsin B-likeCathepsin L-likeFalcipain (in Plasmodium)Cruzipain (in Trypanosoma cruzi)Protease family C1

Inhibition of proteolytic (protein-degrading) activity by covalent or non-covalent blockade of the catalytic cysteine residue