Simultaneous lack of catalase and beta-toxin in Staphylococcus aureus leads to increased intracellular survival in macrophages and epithelial cells and to attenuated virulence in murine and ovine models

• DOI: 10.1099/mic.0.025544-0
• Publication Date: 2009-04-27T22:32:56Z
• Authors: Susana Martínez-P...; Gustavo Domínguez...; José A. Orden; Ricardo de la Fuente
• Keywords: Virulence factor; Hemolysin; Intracellular parasite

Staphylococcus aureus produces a variety of virulence factors that allow it to cause wide range infections in humans and animals. In the latter, S. is leading intramammary infections. The contribution catalase (KatA), an enzyme implicated oxidative stress resistance, beta-toxin (Hlb), haemolysin, pathogenesis poorly characterized. To investigate role these enzymes as potential aureus, we examined intracellular survival DeltakatA, Deltahlb DeltakatA mutants murine macrophages (J774A.1) bovine mammary epithelial cells (MAC-T), their different ovine models. Catalase was not required for within either J774A.1 or MAC-T cells. However, necessary proliferation bacterium after invasion addition, needed full mice. Deletion hlb gene had no effect on but did slight increase Furthermore, like catalase, complete Unexpectedly, mutant showed notably increased persistence both cell lines, significantly less virulent mice than were wild-type strain single mutants. Most interestingly, also markedly attenuated subcutaneous ewes lambs.