Characterization of a novel phage vB_EcoP_P64441 and its potential role in controlling uropathogenic Escherichia coli (UPEC) and biofilms formation.

Urinary tract infections are one of the most common infectious diseases worldwide, with uropathogenic Escherichia coli (UPEC) being the leading cause. Phage therapy has emerged as a promising alternative due to the increasing prevalence of multidrug resistance UPEC strains. In this study, we isolated and characterized a novel phage, vB_EcoP_P64441, which lysed UPEC, including serogroup O75. The phage can survive from 4 to 50 °C and a pH range of 3-11. The optimal MOI was 1, latent period was 4 min, and burst size was 10 PFU/cell. Whole genome sequencing revealed that it consisted of 42,960 base pairs that encoded 53 CDSs, with no lysogenic, toxin, or tRNA-associated genes detected. vB_EcoP_P64441 was classified as a new species within the family Autographiviridae, subfamily Slopekvirinae. The results of the inhibition experiments showed that vB_EcoP_P64441 had a good suppression effect on the growth of planktonic UPEC. Phage either alone or in combination with cefotaxime was effective in inhibiting biofilm formation of UPEC in vitro. Phage strongly inhibited bacterial growth on disposable rubber catheters and limited biofilm formation within 24 h. Cellular infection experiments showed that pretreatment phage could effectively inhibit UPEC adhesion to bladder epithelial cells with safety and reduce the cellular damage caused by UPEC. Our results suggest that vB_EcoP_P64441 is a novel and effective phage for UPEC inhibition with promising applications.