Acinetobacter baumannii is a common bacterial pathogen in nosocomial infections. It has become one of the greatest threats to human health for its growing resistance to “last resort” antibiotics, which has led to a revival of phage therapy as a potential treatment. However, conventional methods for isolating A. baumannii-infecting phages are labor-intensive and often unsuccessful.
Methods:
Our approach involves a computational pipeline to identify temperate phages (prophages) integrated into A. baumannii genomes, followed by mitomycin C (MMC) induction of those strains to screen for active prophages.
Results:
Here we show a prophage analysis for nearly 900 A. baumannii genomes. We observed MMC-triggered excision of nine prophages from eight A. baumannii strains by Polymerase Chain Reaction (PCR) and sequencing. Further, we show four prophage-formed virions detectable by transmission electron microscopy and two that can plaque on other A. baumannii isolates.
Conclusion:
This work demonstrates the utility and diversity of prophages for further development as therapeutics for antibiotic-resistant A. baumannii.
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