Biological and genomic characterization of Escherichia phage KBU_SV1 active against carbapenem-resistant Escherichia coli
5 affiliations
- 1Vocational School of Health Services, Karabük University
- 2Recombinant DNA and Recombinant Protein Research and Application Center (REDPROM), Aydın Adnan Menderes University
- 3VETAL Animal Health Products Inc.
- 4Department of Medical Microbiology, Faculty of Medicine, Aydın Adnan Menderes University
- 5Department of Medical Microbiology, Faculty of Medicine, Kocaeli University
Abstract
Carbapenem-resistant Escherichia coli infections are increasingly difficult to treat, and bacteriophages have been highlighted as a promising tool to control such multidrug-resistant bacteria. Here, we isolated and characterized Escherichia phage KBU_SV1 using E. coli ATCC 25922 as the isolation and propagation host. Its morphology, host range, stability at various temperatures and pH, reduction growth of bacteria, effect on biofilm, in vivo efficacy, and genome were investigated. Transmission electron microscopy showed a polyhedral head and a long, non-contractile tail, corresponding to a siphovirus morphotype. The spot-test analysis of 106 bacterial strains showed spot clearance against 16 strains (host range index, 0.15), including carbapenem-resistant and carbapenem-susceptible E. coli isolates and, to a lesser extent, Klebsiella pneumoniae , while no such effect was observed in the other species tested. KBU_SV1 was stable between pH 4 and 12 and at 4–37 °C, but no infectivity was detected at pH 2 or 65 °C. Bacterial growth was suppressed at all multiplicities of infection (MOI) tested (100–0.01), followed by gradual regrowth. KBU_SV1 reduced established biofilms and inhibited biofilm formation in both E. coli ATCC 25922 and the carbapenem-resistant isolate Ec59. In the Galleria mellonella infection model, phage treatment significantly delayed larval mortality compared with the infection control, while no mortality occurred in larvae receiving phage alone. The genome of KBU_SV1 was found to be 45,190 bp with a G + C content of 53.56% and was complete with a 272-bp direct terminal repeat. The genome contains 71 putative open reading frames (ORFs) and no tRNA, while no virulence, antibiotic resistance (AMR) or lysogeny-associated genes were identified, and genome-based analyses predicted a virulent lifestyle. Comparative genomic analysis showed a high nucleotide identity (99.12%) with Escherichia phage EPIMAM03, and KBU_SV1 was assigned to the genus Dhillonvirus within the class Caudoviricetes . All these results showed that KBU_SV1 has favorable properties such as antibacterial potential against carbapenem-resistant E. coli , broad stability, antibiofilm and in vivo activity, and the absence of virulence and AMR genes. Based on all these features, this newly isolated phage is promising for the control of carbapenem-resistant E. coli infections, alone or in phage cocktails.
Related
- Genomic characterization of carbapenem-resistant organisms from pediatric patients with hematological malignancies and genomic comparison of infection versus intestinal colonizing strains
- Genomic characteristics of a carbapenem-resistant NDM-1-producing Aeromonas caviae isolate from extraintestinal infection
- Model-based evaluation of Targeted-Antibacterial-Plasmids (TAPs) transfer kinetics and resensitization of pOXA-48 carbapenem-resistant Escherichia coli
- Cross-species convergence of surface polysaccharides shapes the virulence of an atypical carbapenem resistant uropathogenic Escherichia coli clone
- Genomic insight into the antibiotic-resistant determinants of Escherichia coli from small ruminants and manure in North West Province, South Africa
BibTeX
@article{oztas2026biological,
title = {{Biological and genomic characterization of Escherichia phage KBU_SV1 active against carbapenem-resistant Escherichia coli}},
author = {Sevil Öztaş and Abdulkerim Karaynir and Rumeysa Gulsu Ozkan and Bulent Bozdogan and Devrim Dündar},
journal = {Frontiers in Microbiology},
year = {2026},
month = oct,
doi = {10.3389/fmicb.2026.1927801},
url = {https://www.frontiersin.org/articles/10.3389/fmicb.2026.1927801/full},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Biological and genomic characterization of Escherichia phage KBU_SV1 active against carbapenem-resistant Escherichia coli
AU - Sevil Öztaş
AU - Abdulkerim Karaynir
AU - Rumeysa Gulsu Ozkan
AU - Bulent Bozdogan
AU - Devrim Dündar
PY - 2026
DA - 2026/10/15
JO - Frontiers in Microbiology
DO - 10.3389/fmicb.2026.1927801
UR - https://www.frontiersin.org/articles/10.3389/fmicb.2026.1927801/full
AB - Carbapenem-resistant Escherichia coli infections are increasingly difficult to treat, and bacteriophages have been highlighted as a promising tool to control such multidrug-resistant bacteria. Here, we isolated and characterized Escherichia phage KBU_SV1 using E. coli ATCC 25922 as the isolation and propagation host. Its morphology, host range, stability at various temperatures and pH, reduction growth of bacteria, effect on biofilm, in vivo efficacy, and genome were investigated. Transmission electron microscopy showed a polyhedral head and a long, non-contractile tail, corresponding to a siphovirus morphotype. The spot-test analysis of 106 bacterial strains showed spot clearance against 16 strains (host range index, 0.15), including carbapenem-resistant and carbapenem-susceptible E. coli isolates and, to a lesser extent, Klebsiella pneumoniae , while no such effect was observed in the other species tested. KBU_SV1 was stable between pH 4 and 12 and at 4–37 °C, but no infectivity was detected at pH 2 or 65 °C. Bacterial growth was suppressed at all multiplicities of infection (MOI) tested (100–0.01), followed by gradual regrowth. KBU_SV1 reduced established biofilms and inhibited biofilm formation in both E. coli ATCC 25922 and the carbapenem-resistant isolate Ec59. In the Galleria mellonella infection model, phage treatment significantly delayed larval mortality compared with the infection control, while no mortality occurred in larvae receiving phage alone. The genome of KBU_SV1 was found to be 45,190 bp with a G + C content of 53.56% and was complete with a 272-bp direct terminal repeat. The genome contains 71 putative open reading frames (ORFs) and no tRNA, while no virulence, antibiotic resistance (AMR) or lysogeny-associated genes were identified, and genome-based analyses predicted a virulent lifestyle. Comparative genomic analysis showed a high nucleotide identity (99.12%) with Escherichia phage EPIMAM03, and KBU_SV1 was assigned to the genus Dhillonvirus within the class Caudoviricetes . All these results showed that KBU_SV1 has favorable properties such as antibacterial potential against carbapenem-resistant E. coli , broad stability, antibiofilm and in vivo activity, and the absence of virulence and AMR genes. Based on all these features, this newly isolated phage is promising for the control of carbapenem-resistant E. coli infections, alone or in phage cocktails.
SN - 1664-302X
ER -