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ARS Home » Pacific West Area » Albany, California » Western Regional Research Center » Produce Safety and Microbiology Research » Research » Publications at this Location » Publication #417563
Research Project: Elucidating the Factors that Determine the Ecology of Human Pathogens in Foods

Location: Produce Safety and Microbiology Research

Title: Bacteriophage Indie resensitizes multidrug-resistant Acinetobacter baumannii to antibiotics in vitro

Author
item OROZCO-OCHOA, ALMA - Center For Research In Food And Development (CIAD)
item GONZALEZ-GOMEZ, JEAN - Center For Research In Food And Development (CIAD)
item Quinones, Beatriz
item CASTRO DEL CAMPO, NOHELIA - Center For Research In Food And Development (CIAD)
item VALDEZ-TORRES, JOSE - Center For Research In Food And Development (CIAD)
item CHAIDEZ-QUIROZ, CRISTOBAL - Center For Research In Food And Development (CIAD)

Submitted to: Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/31/2025
Publication Date: 4/4/2025
Citation: Orozco-Ochoa, A.K., Gonzalez-Gomez, J.P., Quinones, B., Castro Del Campo, N., Valdez-Torres, J.B., Chaidez-Quiroz, C. 2025. Bacteriophage Indie resensitizes multidrug-resistant Acinetobacter baumannii to antibiotics in vitro. Scientific Reports. 15. Article 11578. https://doi.org/10.1038/s41598-025-96669-1.
DOI: https://doi.org/10.1038/s41598-025-96669-1

Interpretive Summary: Antimicrobial resistance is an escalating public health concern, and the World Health Organization has designated it as one of the top global threats. To combat antimicrobial resistance in the food and clinical pathogen Acinetobacter baumannii, phage therapy have proven to be a promising strategy which primarily stems from the phages’ precise targeting of specific bacterial strains and low toxicity for clinical applications. This study characterized a new lytic bacteriophage and demonstrated that combining phage with specific antibiotics resulted in a superior bactericidal effect compared to each agent alone against the pathogen A. baumannii.

Technical Abstract: Phage therapy has re-emerged as a promising alternative to antimicrobial resistance, with phage-antibiotic synergy (PAS) as a potential strategy against the critical pathogen Acinetobacter baumannii. In this study, lytic phage Indie, which shows therapeutic potential against multidrug-resistant A. baumannii, was successfully isolated and characterized. An in vitro PAS study was developed where ceftazidime and piperacillin-tazobactam were chosen as antimicrobials. This research is the first to report a significant synergy (P < 0.05) between phage Indie and ceftazidime at a lower dose of phage and antibiotic. Notably, phage Indie restored the bacterial sensitivity of A. baumannii AbAK03 to ceftazidime and eradicated A. baumannii (>85%) at lower doses (phage: 105 PFU/mL, ceftazidime: 1.6 µg/mL) for 17 h, surpassing the initial resistance in 4 h. This study marks a major advance in phage therapy, allowing efficient determination of optimal phage and antibiotic doses for future in vivo trials and promoting broader therapy adoption.