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Published on: June 30, 2023
PhageScore-based analysis of Acinetobacter baumannii infecting phages antibiotic interaction in liquid medium
Bartłomiej Grygorcewicz1,2, Marta Roszak3, Rafał Rakoczy4
1Chair of Microbiology, Department of Laboratory Medicine, Immunology and Laboratory Medicine, Pomeranian Medical University in Szczecin, Powstańców Wielkopolskich 72, 70-111, Szczecin, Poland. bartlomiej.grygorcewicz@pum.edu.pl.
Abstract:
The growing interest in bacteriophages and antibiotics' combined use poses new challenges regarding this phenomenon's accurate description. This study aimed to apply the PhageScore methodology to assess the phage-antibiotic combination activity in liquid bacterial culture. For this purpose, previously described Acinetobacter infecting phages vB_AbaP_AGC01, Aba-1, and Aba-4 and antibiotics (gentamicin, ciprofloxacin, meropenem, norfloxacin, and fosfomycin) were used to obtain a lysis curve of bacteriophages under antibiotic pressure. The experimental data were analyzed using the Fractional Inhibitory Concentration Index (FICI) and PhageScore methodology. The results obtained by this method clearly show differences between phage lytic activity after antibiotic addition. Thus, we present the potential use of the PhageScore method as a tool for characterizing the phage antibiotic synergy in liquid culture. Further, the optimization of the PhageScore for this purpose can help compare antibiotics and their outcome on bacteriophage lytic activity.
Insights
This study introduces PhageScore to evaluate bacteriophage and antibiotic combinations in liquid cultures. The method accurately measures phage lytic activity under antibiotic influence, aiding in synergy assessment.
Area of Science:
- Microbiology
- Biotechnology
- Pharmacology
Background:
- Bacteriophage and antibiotic combination therapy is gaining interest.
- Accurate assessment methods for phage-antibiotic synergy are needed.
- PhageScore methodology offers a potential solution for evaluating combined activity.
Purpose of the Study:
- To apply the PhageScore methodology for assessing phage-antibiotic combination activity in liquid bacterial culture.
- To analyze phage lytic activity under antibiotic pressure.
- To present PhageScore as a tool for characterizing phage-antibiotic synergy.
Main Methods:
- Utilized Acinetobacter-infecting phages (vB_AbaP_AGC01, Aba-1, Aba-4) and antibiotics (gentamicin, ciprofloxacin, meropenem, norfloxacin, fosfomycin).
- Generated lysis curves of bacteriophages under antibiotic pressure.
- Analyzed experimental data using Fractional Inhibitory Concentration Index (FICI) and PhageScore.
Main Results:
- PhageScore demonstrated clear differences in phage lytic activity following antibiotic addition.
- The methodology effectively characterized phage-antibiotic interactions in liquid culture.
- Observed variations in bacteriophage lytic activity influenced by different antibiotics.
Conclusions:
- PhageScore is a viable tool for characterizing phage-antibiotic synergy in liquid culture.
- Optimization of PhageScore can facilitate comparisons of antibiotic effects on bacteriophage activity.
- This method aids in understanding and developing phage-antibiotic combination therapies.
