Comparative analysis reveals the contribution of phage-derived genomic islands to the increasing pathogenicity of facultative bacterial pathogens

Abstract

Bacteriophages are the most abundant entity in the biosphere outnumbering bacteria by a factor of at least 10. Other than infecting bacteria, phages also influence the evolution of bacteria in an unexpected way to provide more pathogenicity to the species in the course of time. It has thereby become very significant to establish an equation between bacterial increased pathogenicity and phage derived genome islands. Computational analysis of vast number of bacterial pathogenic genomes divided by two different time periods (before and after 1990) yielded the virulence regions emerging from prophages. Notable addition of pathogenic phage proteins was observed in bacteria of the latter time periods indicating increase in the pathogenesis of already pathogenic bacteria. As we have few information on phage diversity and their contribution on bacterial evolution, hence this study would create an opportunity to understand their relationship to a great extent.