Infection and Drug Resistance (Aug 2024)
Isolation and Characterization of Novel Lytic Bacteriophages Infecting Carbapenem-Resistant Pathogenic Diarrheagenic and Uropathogenic Escherichia Coli
Abstract
Kenneth Ssekatawa,1,2 Ibrahim Ntulume,3 Denis Karuhize Byarugaba,3 Slawomir Michniewski,4 Eleanor Jameson,5 Eddie M Wampande,6 Jesca Nakavuma3 1Department of Science Technical and Vocational Education, Makerere University, Kampala, Uganda; 2Africa Center of Excellence in Materials, Product Development and Nanotechnology (MAPRONANO ACE), Makerere University, Kampala, Uganda; 3Department of Biotechnical and Diagnostic Sciences, Makerere University, Kampala, Uganda; 4Centre for Phage Research, University of Leicester, England, UK; 5School of Environmental and Natural Sciences, Bangor University, Gwynedd, UK; 6Department of Veterinary Pharmacy, Clinical and Comparative Medicine, Makerere University, Kampala, UgandaCorrespondence: Kenneth Ssekatawa; Jesca Nakavuma, Email [email protected]; [email protected]; [email protected]: The evolution of antimicrobial resistance has dramatically reduced the efficacy of the first-choice and last-resort antibiotics used to treat E. coli infections. Thus, searching for novel therapeutics to treat and control the emergence of antibiotic resistance is urgent. Therefore, this study aimed to illustrate the lytic effect of phages against carbapenem-resistant pathogenic E. coli.Methods: Phages were isolated from hospital effluents by the enrichment assay. This was followed by the evaluation of the host range of the phages by the spot assay. The time taken by phages to bind to the host bacterial cells was determined by the adsorption assay. The phage latent period and burst size were determined using a one-step growth experiment. Phage morphology was determined by the Transmission Electron Microscopy. Molecular characterization of phages was done by whole genome sequencing.Results: Two phages named UGKSEcP1 and UGKSEcP2 were isolated from hospital effluents. The phages were professionally lytic with a broad host range. The two phages recorded an average adsorption time of 11.25 minutes, an adsorption rate of 99.3%, a latency period of 20 minutes, and a burst size of approximately 528 phages/infected cell. Phages UGKSEcP1 and UGKSEcP2 had genome lengths of 167433bp, and 167221bp with 277 and 276 predicted genes, respectively, and no undesirable genes were detected. Phylogenetic analysis revealed the two phages belonged genus Tequatrovirus. TEM micrograph showed that the two phages had a similar morphotype with icosahedral heads and contractile tails; thus, classified as members of the Myoviridae phage family.Conclusion: The findings demonstrate that the study isolated two novel professionally lytic phages with a broad host range and thus, are candidates for phage-mediated biocontrol.Keywords: antibiotic resistance, carbapenem resistance, bacteriophages
