Complete Genome Sequences of Four Pseudomonas aeruginosa Bacteriophages: Kara-mokiny 8, Kara-mokiny 13, Kara-mokiny 16, and Boorn-mokiny 1.

Pseudomonas aeruginosa is an opportunistic pathogen. Here, we report the isolation of four bacteriophages from wastewater. All four bacteriophages belong to the Myoviridae family. Kara-mokiny 8, 13, and 16 are of the Pbunavirus genus and have genomes between 65,527 and 66,420-bp. Boorn-mokiny 1 is of the Phikzvirus genus and has a 278,796-bp genome.

Development and validation of a miniaturized bacteriophage host range screening assay against antibiotic resistant Pseudomonas aeruginosa.

Antimicrobial resistance is a current global health crisis, and the increasing emergence of multidrug resistant infections has led to the resurgent interest in bacteriophages as an alternative treatment. Prior to clinical application, phage suitability is assessed, via susceptibility testing and breadth of host range to bacteriophage, however, these are both large-scale manual processes and labor-intensive. The aim of the study was to establish and validate a scaled down methodology for high-throughput screening to reduce procedural footprint. In this paper, we describe a scaled-down adapted methodology that can successfully screen bacteriophages, isolated and purified from wastewater samples. Furthermore, we describe a miniaturized host range assay against clinical Pseudomonas aeruginosa isolates using a spot test (2 µL/ drop) that was found to be both sensitive (94.6%) and specific (94.7%). It also demonstrated a positive predictive value (PPV) of 86.4% and negative predictive value (NPV) of 98%. The breadth of host range of bacteriophages that exhibited lytic activity on P. aeruginosa isolates was corroborated using the scaled down assay. The high correlation achieved in this study confirms miniaturization as the first step in future automation that could test phage diversity and efficacy as antimicrobials.

Pseudomonas aeruginosa Resistance to Bacteriophages and Its Prevention by Strategic Therapeutic Cocktail Formulation.

Antimicrobial resistance poses a significant threat to modern healthcare as it limits treatment options for bacterial infections, particularly impacting those with chronic conditions such as cystic fibrosis (CF). Viscous mucus accumulation in the lungs of individuals genetically predisposed to CF leads to recurrent bacterial infections, necessitating prolonged antimicrobial chemotherapy. Pseudomonas aeruginosa infections are the predominant driver of CF lung disease, and airway isolates are frequently resistant to multiple antimicrobials. Bacteriophages, or phages, are viruses that specifically infect bacteria and are a promising alternative to antimicrobials for CF P. aeruginosa infections. However, the narrow host range of P. aeruginosa-targeting phages and the rapid evolution of phage resistance could limit the clinical efficacy of phage therapy. A promising approach to overcome these issues is the strategic development of mixtures of phages (cocktails). The aim is to combine phages with broad host ranges and target multiple distinct bacterial receptors to prevent the evolution of phage resistance. However, further research is required to identify and characterize phage resistance mechanisms in CF-derived P. aeruginosa, which differ from their non-CF counterparts. In this review, we consider the mechanisms of P. aeruginosa phage resistance and how these could be overcome by an effective future phage therapy formulation.