Other genes encoding important virulence factors such as the immunodominant staphylococcal antigen B (isaB), the extracellular fibrinogen binding protein Efb (efb), which is involved in inhibition of phagocytosis33, the pore-forming cytolysin alpha-toxin (hla), and the amphipathic α-helical phenol-soluble modulins psma1, psma2 and psma3, which can kill host cells by damaging the plasma membrane34, were also expressed by S. aureus to a higher extent during infection of C57BL/6 mice (Fig. 4b). The gene discussed is PSMA1; the disease is infection.