Cysteine protease, which is translocated into infected cells and plays a central role in pathogenesis by cleaving the C-terminus end of the human small GTPase RhoA/ARHA, a regulator of cytoskeleton. Once cleaved, ARHA loses its lipid modification, and is released from the cell membrane, leading to the subsequent disruption of actin cytoskeleton of the host cell. Interacts with human ARHA. In infected cells, it is cytoplasmic. Translocated into the host cell by the type III secretion apparatus with the help of the SycT chaperone (By similarity). Belongs to the peptidase C58 family.