Urine -Derived Bacteriophages as Biocontrol Agents: In Vitro Evaluation of Their Lytic Activity Against Uropathogenic Escherichia coli Clinical Isolates and Implication for Phage Therapy in UTIs

Abstract

The rising cases of multidrug-resistant (MDR) infections have necessitated the World Health Organization (WHO) to reiterate the need to find alternative antimicrobial measures. Bacteriophage therapy is one of such options that gain popularity. This study evaluates the therapeutic capabilities of bacteriophages that have been directly obtained out of the urine of patients with the clinical diagnosis of urinary tract infections (UTIs). Two out of five positive cultures of urine samples that produced positive cultures of the bacteria were lysogenized to obtain lytic phages. The temperate bacteriophages were found to have a strong lytic capability against 13 out of 15 MDR Escherichia coli clinical isolates. The presence of resistance in two isolates highlights the interplay of forces that are complex to determine phage-bacterial interactions that may be mediated by genetic processes (CRISPR-Cas systems or mutations in receptors). Notably, the lytic spectrum was expanded by the use of phage cocktails. Transmission electron microscopy (TEM) analysis has shown that the phages that have been isolated are of Myoviridae and Podoviridae family. While purified phages exhibited specificity for Escherichia coli, raw urine samples contained phages capable of lysing other uropathogens, such as Klebsiella pneumoniae, Enterobacter spp., and Serratia spp. This indicates that the reservoir of human urine can be varied and individualized bacteriophages in extreme infection, hence highlighting the prospect of urine-derived phage to develop patient-specific targeted therapies, of special importance in areas where resistance to antibiotics is a major health concern on the part of the population