Commercial Biocides Induce Transfer of Prophage ?13 from Human Strains of Staphylococcus aureus to Livestock CC398.

ABSTRACT: Human strains of Staphylococcus aureus commonly carry the bacteriophage ?Sa3 that encodes immune evasion factors. Recently, this prophage has been found in livestock-associated, methicillin resistant S. aureus (MRSA) CC398 strains where it may promote human colonization. Here, we have addressed if exposure to biocidal products induces phage transfer, and find that during co-culture, ?13 from strain 8325, belonging to ?Sa3 group, is induced and transferred from a human strain to LA-MRSA CC398 when exposed to sub-lethal concentrations of commercial biocides containing hydrogen peroxide. Integration of ?Sa3 in LA-MRSA CC398 occurs at multiple positions and the integration site influences the stability of the prophage. We did not observe integration in hlb encoding ?-hemolysin that contains the preferred ?Sa3 attachment site in human strains, and we demonstrate that this is due to allelic variation in CC398 strains that disrupts the phage attachment site, but not the expression of ?-hemolysin. Our results show that hydrogen peroxide present in biocidal products stimulate transfer of ?Sa3 from human to LA-MRSA CC398 strains and that in these strains prophage stability depends on the integration site. Knowledge of ?Sa3 transfer and stability between human and livestock strains may lead to new intervention measures directed at reducing human infection by LA-MRSA strains.

SUBMITTER: Tang Y 

PROVIDER: S-EPMC5726172 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature