Evolution of a small phage protein overcomes antiphage defense in Enterococcus faecalis

摘要: The prevalence of multidrug resistant (MDR) bacterial infections continues to rise as the development of new antibiotics needed to combat these infections remains stagnant. MDR enterococci, which are a common cause of hospital-acquired infections, are emerging as one of the major contributors to this crisis. A potential therapeutic approach for combating MDR enterococci is bacteriophage (phage) therapy, which entails the use of lytic viruses to infect and kill pathogenic bacteria. While phages that lyse some strains of MDR enterococci have been identified, other strains display high levels of phage resistance and the mechanisms underlying this resistance are unknown. Here, we use a CRISPR interference (CRISPRi) screen to identify a genetic locus found on a mobilizable plasmid from vancomycin-resistant Enterococcus faecalis involved in phage resistance. This locus encodes a putative serine recombinase …