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Isolation and Genome Analysis of Single Virions using 'Single Virus Genomics'
Published on: May 26, 2013
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First detection and genomics analysis of KPC-2-producing Citrobacter isolates from river sediments
1Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China.
Environmental Pollution (Barking, Essex : 1987)
|January 24, 2018
Summary
Carbapenemase-producing Citrobacter, a type of bacteria, were found in Chinese river sediment. These environmental bacteria carry genes for carbapenemase production, raising concerns about the spread of antimicrobial resistance to humans.
Area of Science:
- Environmental microbiology
- Molecular biology
- Public health
Background:
- Carbapenemase-producing Enterobacteriaceae (CPE) are a growing environmental concern.
- Carbapenemase-producing Citrobacter in the environment are understudied.
- Antimicrobial resistance (AMR) poses a significant public health threat.
Purpose of the Study:
- To isolate and characterize carbapenemase-producing Citrobacter from river sediment in China.
- To investigate the genetic relatedness and plasmid-mediated resistance mechanisms.
- To assess the potential for environmental dissemination of AMR genes.
Main Methods:
- Isolation of potential CPE using selective MacConkey agar with meropenem.
- Detection of carbapenemase genes via PCR and sequencing.
- Genotyping (PFGE, MLST) and whole-genome sequencing for clonal relatedness and plasmid analysis.
- Conjugation experiments to assess gene transfer.
Main Results:
- Four Klebsiella pneumoniae carbapenemase (KPC-2)-producing Citrobacter and three Aeromonas isolates were recovered from river sediment near a wastewater treatment plant.
- Three Citrobacter isolates exhibited multidrug resistance.
- The blaKPC-2 gene was located on IncF or IncN3 plasmids and was transferable to E. coli.
- A novel IncF plasmid (pKPC-191) carrying the blaKPC-2 gene was identified.
Conclusions:
- This study reports the first isolation and characterization of KPC-2-producing Citrobacter from river sediments in China.
- Environmental Citrobacter harbor diverse, conjugative blaKPC-2 plasmids.
- The findings highlight the potential for environmental dissemination of AMR into clinical settings.
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