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Published on: December 17, 2015
Acidifying bacteria inhibit pathogenic bacteria more strongly with increasing glucose.
Andrea R Dos Santos1, Clément Vulin1, Sara Mitri1
1Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland.
The ISME Journal
|June 27, 2026
Summary
This study shows how harmless bacteria can suppress pathogens by altering pH. Increasing glucose strengthens this effect, offering a new strategy to control infections and reduce antibiotic use.
Area of Science:
- Microbiology
- Community Ecology
- Systems Biology
Background:
- Traditional microbiology targets pathogens directly, neglecting beneficial microbes.
- Microbial communities exhibit complex interactions, including chemical signaling influencing growth.
- Understanding these interactions is key to novel control strategies.
Purpose of the Study:
- To demonstrate manipulating interspecies interactions to control pathogens.
- To combine microbial interactions with antibiotics for pathogen elimination.
- To explore community context for developing efficient microbial control strategies.
Main Methods:
- Experimental manipulation of bacterial co-cultures.
- Mathematical modeling of microbial interactions.
- pH and glucose concentration measurements.
Main Results:
- Citrobacter freundii suppressed Pseudomonas aeruginosa by reducing pH.
- Increased glucose concentrations enhanced the inhibitory effect of C. freundii.
- The approach was effective against Klebsiella pneumoniae, Agrobacterium tumefaciens, and Lactobacillus plantarum.
Conclusions:
- Harnessing microbial community dynamics offers a potent strategy for pathogen control.
- This approach can reduce reliance on traditional antibiotics.
- Manipulating interspecies chemical interactions provides a novel avenue for therapeutic interventions.
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