Beta toxin catalyzes formation of nucleoprotein matrix in staphylococcal biofilms

摘要: Biofilms are surface-associated communities of microbes encompassed by an extracellular matrix. It is estimated that 80% all bacterial infections involve biofilm formation, but the structure and regulation biofilms incompletely understood. Extracellular DNA (eDNA) a major structural component in many pathogenic bacterium Staphylococcus aureus, its role enigmatic. Here, we demonstrate beta toxin, neutral sphingomyelinase virulence factor S. forms covalent cross-links to itself presence (we refer this as ligase activity, independent activity) producing insoluble nucleoprotein matrix vitro. Furthermore, show toxin strongly stimulates formation vivo demonstrated causation infectious endocarditis rabbit model. Together, these results suggest cross-linking eDNA assists forming skeletal framework upon which staphylococcal established.