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Updated: May 12, 2026
05:18
High-Resolution Comparison of Bacterial Conjugation Frequencies
Published on: January 10, 2019
Integrons: Vehicles and pathways for horizontal dissemination in bacteria
Sara Domingues1, Gabriela J da Silva, Kaare M Nielsen
1Centre of Pharmaceutical Studies; Faculty of Pharmacy; University of Coimbra; Coimbra, Portugal ; Department of Pharmacy; Faculty of Health Sciences; University of Tromsø; Tromsø, Norway.
Mobile Genetic Elements
|April 4, 2013
Summary
Class 1 integrons, genetic elements found in bacteria, spread through mobile genetic elements and other mechanisms. Their dissemination depends on factors like genetic stability and host fitness costs.
Area of Science:
- Microbiology
- Genetics
- Molecular Biology
Background:
- Integrons are genetic elements discovered in the late 1980s.
- Initially found in clinical settings, integrons are now identified in diverse environments like soil and water.
- Approximately 10% of sequenced bacterial genomes contain integrons, often associated with mobile genetic elements (MGEs).
Purpose of the Study:
- To review the factors governing the dissemination of class 1 integrons in bacterial populations.
- To explore the mechanisms of horizontal transfer and vertical inheritance of class 1 integrons.
- To understand the role of MGEs and other genetic processes in integron dynamics.
Main Methods:
- Literature review of studies on integron dissemination.
- Analysis of genetic linkage between integrons and MGEs.
- Examination of factors influencing horizontal gene transfer and vertical inheritance.
Main Results:
- Class 1 integrons frequently associate with MGEs, facilitating their horizontal transfer.
- Transfer of class 1 integrons can occur independently of MGEs through trans-acting factors and homologous recombination.
- Vertical inheritance of transferred MGEs carrying integrons is crucial for sustained dissemination.
Conclusions:
- The spread of class 1 integrons is influenced by MGE transfer, host-independent mechanisms, and heritability.
- Genetic stability and fitness costs to the host are key determinants of integron dissemination.
- Understanding these factors is essential for predicting and controlling the spread of class 1 integrons.
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