Distribution of prophages in the Streptococcus bacteria genus and their role in increasing host pathogenicity

Bacteriophages are a category of viruses that only infect bacteria. Virulent phages cause the cell to produce new phages and lyse, while temperate phages remain in a latent state following phage lysogeny and integration of genetic material into the host genome as prophages. This integration enhances the genetic diversity of the host species, and the new genetic material may offer advantageous traits to aid the host’s survival and adaptation to new environments. Streptococcus bacteria are pathogens that infect both humans and animals, causing invasive infections and a diverse set of diseases. We hypothesized that strains of Streptococcus that have prophages present in their genome are linked to increased pathogenicity or antibiotic resistance. We used PhageWeb to identify prophages found within the 819 strains of Streptococcus genus from GenBank and the distribution of prophages across different species within the genus. With the Progressive Mauve software, we compared the sequences of identified prophages to determine similarities and relationships between the different prophages. Ultimately, based on information from gene ontology databases, we found that different prophages were associated with various virulence factors, adherence factors, and antibiotic resistance genes in their respective bacteria. Bacterial strains containing these prophages may have increased pathogenicity and the embedded genes could have a role in bacterial survivability in different environments. This genetic variation and these prophage characteristics shed light on the evolutionary dynamics of these bacteria species and can be applied to phage therapy.