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Phage-antibiotic synergism: a possible approach to combatting Pseudomonas aeruginosa

Petar Knezevic1, Sanja Curcin, Verica Aleksic

  • 1Department of Biology and Ecology, University of Novi Sad, Trg Dositeja Obradovica 2, Novi Sad, Vojvodina, Serbia. petar.knezevic@dbe.uns.ac.rs

Research in Microbiology
|September 25, 2012
PubMed

Insights

Combining bacteriophages with subinhibitory antibiotic concentrations shows promise for treating Pseudomonas aeruginosa infections. Specifically, ceftriaxone and a Siphoviridae phage demonstrated synergistic effects, reducing bacterial growth and offering new therapeutic strategies.

Area of Science:

  • Microbiology
  • Antimicrobial Resistance
  • Bacteriophage Therapy

Background:

  • Pseudomonas aeruginosa is a resilient opportunistic pathogen causing significant infections.
  • Bacteriophages are increasingly studied as alternative antimicrobial agents against P. aeruginosa.
  • Antibiotic resistance necessitates novel treatment approaches.

Purpose of the Study:

  • To evaluate the antimicrobial effectiveness of combining P. aeruginosa-specific bacteriophages with subinhibitory antibiotic concentrations.
  • To investigate potential synergistic interactions between phages (Podoviridae, Siphoviridae) and antibiotics (gentamicin, ceftriaxone, ciprofloxacin, polymyxin B).

Main Methods:

  • Utilized the time-kill curve method to assess bacterial growth inhibition.
  • Tested combinations of P. aeruginosa bacteriophages and subinhibitory antibiotic concentrations.
  • Observed morphological changes in bacteria post-antibiotic treatment.

Main Results:

  • Combination of bacteriophages and subinhibitory ceftriaxone generally reduced P. aeruginosa growth.
  • Synergistic antimicrobial effect was observed with a Siphoviridae phage (σ-1) and ceftriaxone after 300 minutes.
  • Ceftriaxone induced cell elongation, a morphological change potentially linked to synergism.

Conclusions:

  • Phage-antibiotic combinations, particularly with ceftriaxone, can enhance antimicrobial activity against P. aeruginosa.
  • The observed synergism suggests a promising avenue for developing new therapeutic strategies.
  • Further research into phage-antibiotic synergy could combat lethal P. aeruginosa infections.

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