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Antimicrobial Synergy Testing by the Inkjet Printer-assisted Automated Checkerboard Array and the Manual Time-kill Method
Published on: April 18, 2019
Cefdinir reprograms Gram-positive bacteria to synergize with lysozyme against superbugs
Qi Zhang1,2, Yang Yang1,2, Shuqi Li1
1State Key Laboratory of Chemical Biology and Drug Discovery, Department of Applied Biology and Chemical Technology The Hong Kong Polytechnic University Hong Kong China.
Mlife
|July 3, 2026
Summary
Cefdinir combined with lysozyme targets multidrug-resistant bacteria by altering cell walls, restoring antibiotic efficacy without resistance. This novel approach shows promise for treating Gram-positive superinfections.
Area of Science:
- Microbiology
- Biochemistry
- Pharmacology
Background:
- Multidrug-resistant (MDR) bacteria present a significant global health challenge.
- Cefdinir, a third-generation cephalosporin, faces clinical obsolescence due to resistance.
- Conventional understanding classifies cefdinir as a cell wall synthesis inhibitor.
Purpose of the Study:
- To investigate the mechanism of cefdinir's action against MDR bacteria.
- To evaluate the synergistic potential of cefdinir with lysozyme.
- To explore a novel strategy for combating Gram-positive superbugs.
Main Methods:
- Post-transcriptional analysis of lipoteichoic acid (LTA) and wall teichoic acid (WTA) synthesis pathways.
- Mass spectrometry to identify key enzymes (e.g., TarS).
- In vitro and in vivo antibacterial efficacy testing in cell-based and rat models.
Main Results:
- Cefdinir renders bacterial cell walls negatively charged, enhancing lysozyme synergy.
- Combination therapy restored efficacy against MDR Gram-positive bacteria without inducing resistance.
- Significant suppression of biofilm formation and reduced de novo resistance mutations observed.
Conclusions:
- Cefdinir acts as a sensitizer, not just a synthesis inhibitor, by remodeling cell walls.
- The cefdinir-lysozyme combination offers a promising strategy against MDR Gram-positive infections.
- Clinical translation is feasible due to established safety profiles of both agents.
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