Intragenomic conflict between transformation and prophage explains taxon-specific DNA acquisition.

Prophage content in bacterial isolates is negatively associated with homologous recombination rates, indicating a taxon-specific intragenomic conflict influencing DNA acquisition.

• Why it matters: Understanding how mobile genetic elements and recombination processes interact is crucial for grasping bacterial genome evolution and the dynamics of horizontal gene transfer, which impact adaptation and pathogenicity.
• What they did: The study compared isolates' prophage content and homologous recombination rates across taxa, and tested how extracellular DNA from different species affects prophage activation and deletion in a lysogen.
• The result: Findings show that DNA from the same species promotes prophage activation and deletion, while DNA from different species only triggers activation; recombination is more common when DNA comes from fewer donor species.