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Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes
Published on: March 3, 2023
Multiple antimicrobial resistance in Enterobacteriaceae isolates from pristine freshwater.
C I Lima-Bittencourt1, L Cursino, H Gonçalves-Dornelas
1Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil.
Genetics and Molecular Research : GMR
|November 7, 2007
Summary
Freshwater bacteria commonly show resistance to multiple antimicrobials, varying by season but not by specific bacterial types or water conditions. This widespread antimicrobial resistance in freshwater enterobacteria highlights potential risks for horizontal gene spread.
Area of Science:
- Environmental microbiology
- Antimicrobial resistance
- Bacterial genetics
Background:
- Freshwater ecosystems harbor diverse bacterial communities, including enterobacteria, which can be reservoirs of antimicrobial resistance genes.
- Understanding the factors influencing antimicrobial resistance in these environments is crucial for public health and ecological balance.
Purpose of the Study:
- To investigate antimicrobial and mercury resistance patterns in a freshwater enterobacterial population.
- To explore the association between resistance patterns and biotic/abiotic environmental factors.
- To assess the prevalence of multidrug resistance and the bla(TEM) gene.
Main Methods:
- Conventional biochemical tests for bacterial identification.
- Antimicrobial susceptibility testing.
- Analysis of water samples for pH, temperature, and chlorophyll a concentration.
Main Results:
- Identified 10 genera of freshwater enterobacteria, including Klebsiella, Serratia, and Escherichia.
- Sixty-one percent of isolates exhibited resistance to multiple antimicrobials, with higher prevalence during the rainy season (100%) compared to the dry season (89%).
- No correlation was found between resistance patterns and bacterial genera or environmental factors (pH, temperature, chlorophyll a).
Conclusions:
- Seasonal variations significantly impact antimicrobial resistance in freshwater enterobacteria.
- The high prevalence of multidrug resistance and the presence of the bla(TEM) gene suggest a significant role for freshwater enterobacteria in the horizontal spread of resistance.
- Environmental factors like pH, temperature, and chlorophyll a did not directly influence observed resistance patterns.
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