Table III.
Virulence factors with confirmed or putative involvement in the induction of lesions by A. pleuropneumoniae and the corresponding genes.
| (Putative) virulence factor | Gene | Function | Reference |
|---|---|---|---|
| Pore forming RTX toxin I (activator, structural unit, secretion proteins) | apxICABD | Strongly haemolytic; strongly cytotoxic for alveolar macrophages and neutrophils | [42, 50–52, 59, 115] |
| Pore forming RTX toxin II (activator, structural unit) | apxIICA | Weakly haemolytic; moderately cytotoxic for alveolar macrophages and neutrophils | [42, 43, 50–52, 59, 102, 115] |
| Pore forming RTX toxin III (activator, structural unit, secretion proteins) | apxIIICABD | Non-haemolytic, strongly cytotoxic for alveolar macrophages and neutrophils | [42, 43, 50–52, 59, 115] |
| Putative pore forming RTX toxin IV | apxIVA | Uncertain, required for full virulence | [8, 32, 74–76, 101] |
| Lipopolysaccharide biosynthesis | galU, rmlC, rfbN, rfbP, rfbU, rfaE | Enhanced effect of Apx toxins on phagocytes, activation of production of inflammatory cytokines, induction of necrosis in porcine lung epithelial cells | [5, 47, 48, 93, 94] |
| Proteases | NA* | Degradation of porcine gelatin, actin, hemoglobin | [81–83] |
* Information not available.