Features | Partner Sites | Information | LinkXpress
Sign In
GLOBETECH PUBLISHING
JIB
GLOBETECH PUBLISHING

Deadly Drug-Resistant Strain of Escherichia coli Emerged as a Single Genetic Clone

By BiotechDaily International staff writers
Posted on 02 Jan 2014
Image: Colonies of Escherichia coli growing in a laboratory culture (Photo courtesy of the CDC - Centers for Disease Control and Prevention).
Image: Colonies of Escherichia coli growing in a laboratory culture (Photo courtesy of the CDC - Centers for Disease Control and Prevention).
Molecular microbiologists working with advanced genomic research tools have shown that an extremely virulent and drug-resistant strain of Escherichia coli appeared about 10 years ago following mutations in two genes.

Previous studies on the H30-Rx clone of the ST131 strain of E. coli using pulsed-field gel electrophoresis (PFGE) had indicated that characteristics such as propensity for extraintestinal infections, fluoroquinolone resistance, and extended-spectrum beta-lactamase (ESBL) production had arisen as a series of independent genetic events. If this conclusion were correct, it would suggest that the existence of many different intermediate strains would exist with multiple pathways for evading the immune system and medical treatment.

However, in a new study published in the December 17, 2013, edition of the journal mBio, investigators at George Washington University School of Public Health (Washington DC, USA) and their colleagues at the University of Minnesota (Minneapolis, USA) used the advanced genomic technique, whole-genome sequencing, to reconstruct the evolutionary history of the ST131 clone. The investigators analyzed the genomes of samples of E. coli collected from patients and animals in five countries over the 44-year period, 1967–2011.

They found that fluoroquinolone resistance was confined almost entirely to a single, rapidly expanding ST131 subclone, designated H30-R. This clone, which was fully resistant to the drug ciprofloxacin, soon morphed into a new clone called H30-Rx, which was resistant to several extended-spectrum antibiotics, such as third-generation cephalosporins.

The investigators believe that the clonal nature of H30-Rx may provide opportunities for vaccine or transmission prevention-based control strategies, which could gain importance as H30-Rx and other extraintestinal pathogenic E. coli subclones become resistant to an increasing number of antibiotics.

"This strain of E. coli spreads from person to person and seems to be particularly virulent," said contributing author Dr. James R. Johnson, professor of medicine at the University of Minnesota. "This study might help us develop better tools to identify, stop or prevent its spread by finding better ways to block the transmission of the superbug, or by finding a diagnostic test that would help doctors identify such an infection early on, before it might have the chance to turn lethal."

Related Links:

George Washington University School of Public Health
University of Minnesota



comments powered by Disqus

Channels

Drug Discovery

view channel
Image: S-649266 has more robust antibacterial activity than established antibiotics against multidrug-resistant bacteria (Photo courtesy of Shionogi).

Novel Antibiotic Shows Potential for Broad Range of Infections

The emergence of bacterial resistance to known antibacterial agents is becoming a major challenge in treating the infection caused by multi drug resistant (MDR) bacteria. In order to treat bacterial... Read more

Lab Technologies

view channel
Image: Leica Microsystems launches the inverted research microscope platform Leica DMi8 (Photo courtesy of Leica Microsystems).

New Inverted Microscope Designed to Readily Adapt to Changing Research Demands

A new inverted microscope for biotech and other life science laboratories was designed to readily accommodate modifications and upgrades to allow it to keep current with changing research demands and interests.... Read more

Business

view channel

Collaboration of Mayo Clinic and IBM Cognitive Computer Devised to Improve Clinical Trial Research

The Mayo Clinic (Rochester, MN, USA) and IBM (Armonk, NY, USA) recently announced plans to pilot Watson, the IBM cognitive computer, to match patients more rapidly with suitable clinical trials. A proof-of-concept phase is currently ongoing, with the intent to introduce it into clinical use in early 2015.... Read more
 
Copyright © 2000-2014 Globetech Media. All rights reserved.