Comparative analysis of prophages carried by human and animal-associated Staphylococcus aureus strains spreading across the European regions

Abstract

Staphylococcus aureus is a major human and animal pathogen although the animal-associated S. aureus can be a potential risk of human zoonoses. Acquisition of phage-related genomic islands determines the S. aureus species diversity. This study characterized and compared the genome architecture, distribution nature, and evolutionary relationship of 65 complete prophages carried by human and animal-associated S. aureus strains spreading across the European regions. The analyzed prophage genomes showed mosaic architecture with extensive variation in genome size. The phylogenetic analyses generated seven clades in which prophages of the animal-associated S. aureus scattered in all the clades. The S. aureus strains with the same SCCmec type, and clonal complex favored the harboring of similar prophage sequences and suggested that the frequency of phage-mediated horizontal gene transfer is higher between them. The presence of various virulence factors in prophages of animal-associated S. aureus suggested that these prophages could have more pathogenic potential than prophages of human-associated S. aureus. This study showed that the S. aureus phages are dispersed among the several S. aureus serotypes and around the European regions. Further, understanding the phage functional genomics is necessary for the phage-host interactions and could be used for tracing the S. aureus strains transmission.