Features | Partner Sites | Information | LinkXpress
Sign In
GLOBETECH PUBLISHING
GLOBETECH PUBLISHING
PZ HTL SA

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



Channels

Drug Discovery

view channel
Image: Chitosan is derived from the shells of shrimp and other sea crustaceans, including Alaskan pink shrimp, pictured here (Photo courtesy of NOAA - [US] National Oceanic and Atmospheric Administration).

Chitosan Treatment Clears the Way for Antibiotics to Eliminate Recurrent Urinary Tract Infections

Recurrent urinary tract infection was successfully resolved in a mouse model by treatment with the exfoliant chitosan followed by a round of antibiotics. Bacterial urinary tract infection (UTI), most... Read more

Biochemistry

view channel

Mitochondrial Cause of Aging Can Be Reversed

Researchers have found a cause of aging in lab animals that can be reversed, possibly providing an avenue for new treatments for age-related diseases including type 2 diabetes, cancer, muscle wasting, and inflammatory diseases. The researchers plan to begin human trials late 2014. The study, which was published December... Read more

Therapeutics

view channel

Cytokine Identified That Causes Mucositis in Cancer Therapy Patients

The action of the cytokine interleukin 1-beta (IL-1beta) has been found to underlie the onset of mucositis, a common, severe side effect of chemotherapy and irradiation of cancer patients. Mucositis occurs as a result of cell death in reaction to chemo- or radiotherapy. The mucosal lining of the mouth becomes thin, may... Read more

Lab Technologies

view channel
Image: Diagram of the apparatus for testing drug solubility (Photo courtesy of the University of Huddersfield).

Novel Apparatus Mimics the Human Digestive System for Oral Drug Studies

A team of British drug developers has created an instrument that mimics the human digestive system, which will allow them to accurately determine how orally-administered medications are dissolved and then absorbed.... Read more

Business

view channel

Analytical Sciences Trade Fair Declared a Rousing Success

Organizers of this year's 24th "analytica" biosciences trade fair have reported significant increases in both the number of visitors and exhibitors compared to the 2012 event. The analytica trade fair for laboratory technology, analysis, and biotechnology has been held at the Munich (Germany) Trade Fair Center every... Read more
 
Copyright © 2000-2014 Globetech Media. All rights reserved.