Phage discovery from sewage samples targeting Acinetobacter baumannii

The escalating antimicrobial resistance (AMR) crisis, fueled by antibiotic overuse, renders traditional treatments ineffective and poses a global health threat. The search for new therapies is insufficient, with resistance emerging even without direct antibiotic exposure. Alternatives to traditional antibiotics are urgently needed, including bacteriocins, antimicrobial peptides, probiotics, immunomodulators, enzyme inhibitors, novel drug delivery systems, and especially bacteriophages.Bacteriophages, or phages, are viruses that specifically infect and kill bacteria. Ubiquitous in nature, lytic phages, which destroy bacterial cells, show promise against multidrug-resistant (MDR) pathogens like P. aeruginosa, S. aureus, Enterococcus spp., and A. baumannii.Phage therapy offers unique advantages over conventional antibiotics: its specificity minimizes damage to the microbiome, and phages' ability to co-evolve with bacteria allows them to overcome emerging resistance mechanisms, providing long-term therapeutic potential. However, this co-evolution can also lead to the emergence of phage-resistant bacteria. While their high specificity protects the microbiome, it also limits their therapeutic scope, requiring accurate characterization of the infecting strain and potential therapeutic adjustments.Recent studies suggest that phage cocktails, combining multiple phages, can broaden the spectrum of action and reduce resistance development. Advances in genome sequencing and bioinformatics have revolutionized phage characterization, enabling rapid identification of therapeutically suitable phages based on their host range, virulence, and genomic features, leading to more targeted and effective treatments.Our study aims to discover and characterize novel phages targeting MDR A. baumannii that can work synergistically with life-saving antibiotics. We assessed the phages' host range, genomic and morphological features, and interactions with the bacterial host. We also investigated their ability to adapt to new bacterial strains to evaluate their therapeutic potential. To achieve this, we developed a comprehensive and validated workflow, including host selection, phage isolation, genome sequencing, and phage adaptation strategies to enhance therapeutic efficacy.