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Monitoring Intraspecies Competition in a Bacterial Cell Population by Cocultivation of Fluorescently Labelled Strains
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Within-host bacterial growth dynamics with both mutation and horizontal gene transfer
Ramsès Djidjou-Demasse1, Samuel Alizon2, Mircea T Sofonea2
1MIVEGEC, IRD, CNRS, Univ. Montpellier, Montpellier, France. ramses.djidjoudemasse@ird.fr.
Journal of Mathematical Biology
|February 5, 2021
Summary
This study models bacterial antibiotic resistance, revealing how traits like nutrient consumption and mutation rates influence strain survival and coexistence. Understanding these dynamics is key to combating public health threats from resistant bacteria.
Area of Science:
- Microbiology
- Evolutionary Biology
- Mathematical Biology
Background:
- Antibiotic resistance is a significant global health challenge.
- Understanding within-host microbial dynamics is crucial for addressing resistance.
- Key factors include mutation, gene transfer, and resource competition.
Purpose of the Study:
- To analyze a mathematical model of four bacterial strains with varying resistance mechanisms.
- To identify conditions for the existence of stable bacterial populations.
- To explore how bacterial traits affect resistance dynamics.
Main Methods:
- Developed a generic mathematical model for bacterial strain interactions.
- Defined threshold numbers for effective reproduction and transitions.
- Analyzed model dynamics based on bacterial quantitative traits.
Main Results:
- Identified key bacterial traits influencing resistance thresholds (e.g., nutrient consumption, mutation rates, death rates).
- Demonstrated that the order of these thresholds dictates population dynamics.
- Showcased dynamics ranging from total extinction to coexistence of all strains.
Conclusions:
- Bacterial quantitative traits significantly impact antibiotic resistance evolution.
- The model provides insights into microbial dynamics under different drug pressures.
- This framework aids in understanding and potentially controlling antibiotic resistance.
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