Mobilization of Genomic Islands of Staphylococcus aureus by Temperate Bacteriophage.

ABSTRACT: The virulence of Staphylococcus aureus, in both human and animal hosts, is largely influenced by the acquisition of mobile genetic elements (MGEs). Most S. aureus strains carry a variety of MGEs, including three genomic islands (?Sa?, ?Sa?, ?Sa?) that are diverse in virulence gene content but conserved within strain lineages. Although the mobilization of pathogenicity islands, phages and plasmids has been well studied, the mobilization of genomic islands is poorly understood. We previously demonstrated the mobilization of ?Sa? by the adjacent temperate bacteriophage ?SaBov from strain RF122. In this study, we demonstrate that ?SaBov mediates the mobilization of ?Sa? and ?Sa?, which are located remotely from ?SaBov, mostly to recipient strains belonging to ST151. Phage DNA sequence analysis revealed that chromosomal DNA excision events from RF122 were highly specific to MGEs, suggesting sequence-specific DNA excision and packaging events rather than generalized transduction by a temperate phage. Disruption of the int gene in ?SaBov did not affect phage DNA excision, packaging, and integration events. However, disruption of the terL gene completely abolished phage DNA packing events, suggesting that the primary function of temperate phage in the transfer of genomic islands is to allow for phage DNA packaging by TerL and that transducing phage particles are the actual vehicle for transfer. These results extend our understanding of the important role of bacteriophage in the horizontal transfer and evolution of genomic islands in S. aureus.

SUBMITTER: Moon BY 

PROVIDER: S-EPMC4783081 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature