Isolation and Characterization of Jumbo Coliphage vB_EcoM_Lh1B as a Promising Therapeutic Agent against Chicken Colibacillosis

Abstract

Colibacillosis in chickens can cause the death of young stock, decrease weight gain and lead to significant economic losses. Currently, antibiotic therapy is the main method of treatment of infected animals, but unchecked use of antibiotics has led to widespread antibiotic resistance among microorganisms. Therefore, it is necessary to develop alternative methods of treating bacterial infections that are fully consistent with the One Health concept and introduce them into practice. Phage therapy meets the specified requirements perfectly. This study describes the isolation and characterization of the lytic jumbo phage vB_EcoM_Lh1B and evaluates its potential use in controlling antibiotic-resistant E. coli infection in poultry. The complete phage genome is 240,200 bp long. Open reading frame (ORF) prediction shows that the phage genome does not contain genes encoding antibiotic resistance and lysogeny factors. Based on phylogenetic and electron microscopic analysis, vB_EcoM_Lh1B belongs to the group of myoviruses of the Seoulvirus genus of the Caudoviricetes class. The bacteriophage has good resistance to a wide range of pH and temperatures and has the ability to suppress 19 out of 30 studied pathogenic E. coli strains. The biological and lytic properties of the isolated vB_EcoM_Lh1B phage make it a promising target of further study as a therapeutic agent against E. coli infections in poultry.

Choice of Ultrafilter Affects Recovery Rate of Bacteriophages

“…However, as a consequence, small bacterial species such as Polynucleobacter and some Actinobacteria [ 54 , 55 ] may also pass through the filter. Choosing a smaller pore size (such as the 0.22 μm filter) can minimize this contamination, but will cause the exclusion of viruses above 220 nm in diameter, such as giant viruses and larger phages [ 56 , 57 ].…”

Evaluation of phage cocktail efficacy for controlling infections caused by pathogenic Escherichia coli in in vivo experiments

“…Uz was confirmed as an E. coli using the Biolog GEN III biochemical test panel, according to the manufacturer's protocol (Biolog, USA). The presence of virulence genes most commonly associated with avian pathogenic E. coli were determined by PCR [13]. E. coli isolate was stored at 4°C in the collection of the Research and Production Center of Microbiology and Virology.…”