A novel virulent Litunavirus phage possesses therapeutic value against multidrug resistant Pseudomonas aeruginosa

Area of Science:

• Microbiology
• Virology
• Bacteriology

Background:

• Pseudomonas aeruginosa is a significant nosocomial pathogen causing severe infections.
• The rise of multidrug-resistant (MDR) P. aeruginosa necessitates alternative treatments like phage therapy.
• Phages offer a targeted approach to combatting bacterial infections.

Purpose of the Study:

• To isolate and characterize a novel Pseudomonas phage for potential therapeutic applications.
• To evaluate the efficacy of the isolated phage against MDR P. aeruginosa strains.
• To assess the phage's safety and specificity for therapeutic use.

Main Methods:

• Isolation of Pseudomonas phage vB_PaeS_VL1 (VL1) from urban sewage.
• Phylogenetic analysis to determine phage classification.
• Lysis assays against MDR P. aeruginosa strains and other bacteria.
• In vitro experiments to assess bacterial load and biofilm reduction.
• In vivo efficacy testing using Galleria mellonella infection models.

Main Results:

• VL1 was identified as a novel species within the Litunavirus genus, confirmed as a virulent phage.
• VL1 lysed 56% of tested MDR P. aeruginosa strains, showing high specificity.
• Significant reduction in bacterial load (approx. 6 log) and pre-formed biofilms (75%) was observed.
• VL1 treatment increased survival rates in infected Galleria mellonella larvae.

Conclusions:

• Phage VL1 exhibits potent lytic activity against MDR P. aeruginosa.
• Its genetic and biological properties suggest it is a strong candidate for phage therapy.
• VL1 demonstrates specificity and efficacy in reducing bacterial burden and enhancing host survival.