Abstract
Abstract Untreated wastewater can retain antimicrobial-resistant bacteria, yet phage performance is inferred from simplified host systems. We evaluated genome-resolved lytic phage ɸPRS-1 against Pseudomonas aeruginosa PAO1 in planktonic and single-strain biofilm assays, wastewater-derived multidrug-resistant P. aeruginosa in same-species mixed-strain biofilms, and raw sewage influent. ɸPRS-1 reduced planktonic PAO1 by 8.67 log₁₀, biofilm-associated PAO1 by 9.83 log₁₀ and cetrimide-selected sewage pseudomonads by 4.2 log₁₀, demonstrating activity across increasing biological and matrix complexity.