The importance of phenol-soluble modulins in Staphylococcus aureus infections

Abstract

Staphylococcus aureus asymptomatically colonise epithelial surfaces of part of the human population. However, when the epithelial barriers breach the bacteria can cause severe infections. The antibiotic resistance and high virulence of some S. aureus strains, especially community-acquired methicillin-resistant S. aureus (CA-MRSA), make infections life-threatening and hard to treat. Recently, it was discovered that CA-MRSA secrete phenol-soluble modulin (PSM) peptides. These leukocidins can recruit neutrophils to the site of infection and enable the bacteria to escape neutrophil phagosomes. Furthermore, PSMs are able to lyse host cells and are also suggested to kill bacterial cells of niche competitors. Finally, the PSM peptides are involved in structuring and detachment of biofilms. In this review, the effects and importance of these PSMs for the virulence of CA-MRSA are discussed.