Related Experiment Video
Updated: Jun 16, 2026
09:00
Testing the Role of Multicopy Plasmids in the Evolution of Antibiotic Resistance
Published on: May 2, 2018
Spread of OXA-48-encoding plasmid in Turkey and beyond
Amélie Carrër1, Laurent Poirel, Mesut Yilmaz
1Service de Bactériologie-Virologie, INSERM U914 Emerging Resistance to Antibiotics, Hôpital de Bicêtre, Assistance Publique/Hôpitaux de Paris, Faculté de Médecine Paris Sud, K.-Bicêtre, France.
Antimicrobial Agents and Chemotherapy
|January 21, 2010
Summary
The OXA-48 carbapenemase gene is spreading globally via plasmids among Enterobacteriaceae. This study identified similar plasmids carrying bla(OXA-48) in isolates from multiple countries, highlighting a significant public health concern.
Area of Science:
- Microbiology
- Molecular Biology
- Infectious Diseases
Background:
- Carbapenem resistance is a growing global health threat.
- OXA-48 carbapenemase is a significant mechanism of resistance in Enterobacteriaceae.
- Previous studies have indicated the presence of OXA-48 in various geographical regions.
Purpose of the Study:
- To analyze carbapenem-resistant Enterobacteriaceae isolates positive for OXA-48.
- To investigate the genetic basis and dissemination of the bla(OXA-48) gene.
- To understand the role of plasmids in the spread of OXA-48 carbapenemase.
Main Methods:
- Analysis of 18 carbapenem-resistant, OXA-48-positive Enterobacteriaceae isolates.
- Plasmid profiling to identify genetic elements carrying the bla(OXA-48) gene.
- Investigation of transposon structures (Tn1999, Tn1999.2) associated with the carbapenemase gene.
Main Results:
- Identical 70-kb plasmids carrying the bla(OXA-48) gene were found in most isolates.
- The bla(OXA-48) gene was located within transposons Tn1999 or Tn1999.2.
- These transposons were consistently inserted within the same host gene across different isolates.
- Isolates were recovered from Turkey, Lebanon, Egypt, France, and Belgium.
Conclusions:
- The findings demonstrate the plasmid-mediated dissemination of OXA-48 carbapenemase.
- The identified genetic structures (plasmids, transposons) are key to the spread of this resistance mechanism.
- This study underscores the worldwide spread of OXA-48 carbapenemase, posing a significant challenge for infection control.
Related Concept Videos
01:27Horizontal Gene Transfer
Horizontal gene transfer (HGT) is a process where genetic material moves between organisms within the same generation, unlike vertical gene transfer, which occurs from parent to offspring. HGT plays a crucial role in microbial evolution, adaptation, and survival, particularly in shared environments like the human gut.Mobile genetic elements such as plasmids, prophages, integrons, insertion sequences, and transposons facilitate this process. HGT occurs through three primary mechanisms:...
01:24Plague
Plague is a highly virulent zoonotic disease caused by Yersinia pestis, a Gram-negative, facultatively anaerobic coccobacillus. This pathogen primarily circulates among rodent populations and is transmitted to humans through the bite of infected fleas. Additional transmission routes include direct contact with infected animal tissue or inhalation of respiratory droplets from individuals with pneumonic plague. These multiple transmission pathways highlight the bacterium’s potential for rapid...
00:57Antibiotic Selection
Overview
01:28Plasmids
Plasmids are extrachromosomal DNA molecules found in bacteria, archaea, and some eukaryotic microbes like yeast. These small, circular DNA structures typically contain fewer than 30 genes, although some may exist linearly. Plasmids vary in their number within a cell, known as copy number. Single-copy plasmids are present in one copy per cell and multi-copy plasmids are present in multiple copies, reaching over 100 copies per cell.Plasmids usually replicate independently of the chromosomal DNA...
01:24Transposons
Transposons, or "jumping genes," are small mobile genetic elements (MGEs) that range from 700 to 40,000 base pairs in length. They are found in all organisms and can move within the same chromosome or transfer to different chromosomes. In some cases, transposons can also jump between different host DNA molecules, such as plasmids or viruses, contributing to genetic variability.Barbara McClintock first discovered these mobile genetic elements in the 1940s while studying maize genetics, and she...
01:30Development of Antibiotic Resistance
Antibiotic resistance is a major public health concern that arises when bacteria evolve mechanisms to withstand the effects of antibiotic treatments. This resistance can be intrinsic, acquired through genetic mutations, or transferred between bacteria via horizontal gene transfer. The development of antibiotic resistance poses significant challenges in treating bacterial infections and necessitates ongoing research to develop new therapeutic strategies.Intrinsic resistance occurs when bacterial...