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Updated: Jun 27, 2026

Antimicrobial Synergy Testing by the Inkjet Printer-assisted Automated Checkerboard Array and the Manual Time-kill Method
12:03

Antimicrobial Synergy Testing by the Inkjet Printer-assisted Automated Checkerboard Array and the Manual Time-kill Method

Published on: April 18, 2019

Synergistic Bactericidal Effects of R- and F-Type Pyocin Cocktails Against Clinical Pseudomonas aeruginosa Isolates

Yi-Luen Shen1,2, Wen-Tong Xu3,4, Zih-Ling Jiang4

  • 1Division of Chest Medicine, Department of Internal Medicine, Asia University Hospital, Asia University, Taichung 413505, Taiwan.

Antibiotics (Basel, Switzerland)
|June 26, 2026
PubMed

Insights

Pyocins show promise against multidrug-resistant Pseudomonas aeruginosa. Serotype variations in lipopolysaccharide (LPS) affect susceptibility, suggesting pyocin cocktails could be a precision medicine approach.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Bacteriophage Therapy

Background:

  • Pseudomonas aeruginosa is a significant cause of healthcare-associated infections.
  • Multidrug-resistant (MDR) strains necessitate novel therapeutic strategies.
  • R- and F-type pyocins are bacteriocins targeting P. aeruginosa.

Purpose of the Study:

  • To determine O-serotype distribution and pyocin susceptibility in P. aeruginosa clinical isolates from Taiwan.
  • To evaluate the therapeutic potential of pyocins against MDR P. aeruginosa.
  • To investigate the correlation between LPS structure and pyocin resistance.

Main Methods:

  • Analysis of 109 ICU-derived P. aeruginosa isolates.
  • O-serotyping by PCR and pyocin gene confirmation by sequencing.
  • Testing pyocin susceptibility using spot assays and SDS-PAGE for LPS profiling.

Main Results:

  • Prevalent serotypes included O6, O2/O5/O16/O18/O20, O1, and O11/O17.
  • Pyocin susceptibility varied significantly by serotype, with O1 and O6 being sensitive and O2/O5/O16/O18/O20 resistant.
  • Resistant isolates had densely packed O-antigens, hindering pyocin binding.
  • R- and F-type pyocin cocktails demonstrated synergistic killing of MDR isolates.

Conclusions:

  • Updated P. aeruginosa serotype profile for Taiwan established.
  • LPS structural variations are critical determinants of pyocin susceptibility.
  • Pyocin cocktails represent a potential precision medicine strategy against MDR P. aeruginosa growth and biofilm formation.
Keywords:
O-serotype distributionPseudomonas aeruginosalipopolysaccharide structuremultiple drug resistantpyocins

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