During the asexual blood stage, processes key proteins essential for merozoite egress and invasion of host erythrocytes (PubMed:29074774). Cleaves and activates proteases SUB1 and SUB2 (PubMed:29074774). May process members of the EBL and Rh protein families (By similarity). Also cleaves apical membrane protein AMA1 (By similarity). During the mosquito vector stage and probably in ookinetes, cleaves CelTOS (By similarity). Inhibited by aminohydantoin compounds such as CWHM-117. In schizonts, localizes to exonemes which are secretory vesicles that discharge their content during egress into the parasitophorous vacuole. Expressed during the asexual blood stage, in schizonts (at protein level). Autocleaved into a p16 prodomain form and two mature forms p44 and p51. Normal asexual development in host erythrocytes; however merozoite egress from erythrocyte is impaired (PubMed:29074774). Erythrocyte invasion by the few newly released merozoites is severly impaired (PubMed:29074774). Impaired SUB1 proteolytic processing (PubMed:29074774). Belongs to the peptidase A1 family.