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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, 5052, 59, 115]
Pore forming RTX toxin II (activator, structural unit) apxIICA Weakly haemolytic; moderately cytotoxic for alveolar macrophages and neutrophils [42, 43, 5052, 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, 5052, 59, 115]
Putative pore forming RTX toxin IV apxIVA Uncertain, required for full virulence [8, 32, 7476, 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 [8183]

* Information not available.