Serine protease which also acts as a protein chaperone (PubMed:24494818). Plays a role in the parasite development in host erythrocytes possibly by protecting it against thermal and oxidative stresses (PubMed:24494818). Oligomer; may form trimers or hexamers (PubMed:24494818). Forms a complex at least composed of DegP, ENO and HSP70 (PubMed:24494818). Localizes to the cytoplasm and cell membrane of host erythrocytes. During the asexual blood stage, expressed in trophozoites, schizonts and free merozoites (at protein level). By heat and oxidative stresses in trophozoites and schizonts (at protein level). The PDZ domain is dispensable for protease and chaperone activities. Belongs to the peptidase S1C family.