One of the virulence factors of A.pleuropneumoniae, which has a strong hemolytic activity and is cytotoxic for alveolar macrophages and neutrophils. The Gly-rich region is probably involved in binding calcium, which is required for target cell-binding or cytolytic activity. The three transmembrane domains are believed to be involved in pore formation by the cytotoxin. Palmitoylated by ApxIC. The toxin only becomes active when modified (By similarity). ApxIA is partially deleted in serotypes 2, 4, 6, 7, 8, 12, and totally deleted in serotype 3. The sequence shown is that of serotype 10. Belongs to the RTX prokaryotic toxin (TC 1.C.11) family.