E. coli bacteria more likely to develop resistance after exposure to low levels of antibiotics

Jun 14, 2011
Microbial Drug Resistance is an authoritative peer-reviewed international journal published quarterly in print and online that covers the growing threat and global spread of antibiotic resistant microbial pathogens and resistance genes. Led by Editor-in-Chief Alexander Tomasz, Ph.D., the Rockefeller University (New York, NY), the journal covers topics that include the molecular biology of resistance mechanisms, virulence genes, and disease, as well as molecular epidemiology, drug design, infection control and medical practice. Credit: © Mary Ann Liebert Inc., publishers

E. coli bacteria exposed to three common antibiotics were more likely to develop antibiotic resistance following low-level antibiotic exposure than after exposure to high concentrations that would kill the bacteria or inhibit their growth, according to a timely article in Microbial Drug Resistance, a peer-reviewed journal published by Mary Ann Liebert, Inc.

E. coli bacteria in food and water supplies have been responsible for disease outbreaks and deaths around the world in recent years. The current outbreak in Europe has sickened thousands of individuals and caused multiple deaths and life-threatening complications in hundreds of persons infected with a new strain of E. coli.

to commonly prescribed antibiotics is an enormous and growing problem, largely due to misuse of antibiotics to treat non-bacterial infections and environmental exposure of the bacteria to low levels of antibiotics used, for example, in agriculture. In the article "De Novo Acquisition of Resistance to Three Antibiotics by Escherichia coli," the authors studied the mechanisms by which E. coli acquire resistance to three common antibiotics: amoxicillin, tetracycline, and enrofloxacin. Depending on the antibiotic and the level of exposure, different mechanisms may come into play. The authors report that exposure to antibiotics at relatively low levels--below those needed to inhibit growth of the bacteria--are more likely to result in the development of . "Exposure to low levels of antibiotics therefore clearly poses most risk," a finding that "contradicts one of the main assumptions made questioning the threat of usage of antibiotics in food animals," conclude the authors.

Explore further: Study provides new insights into the genetics of drug-resistant fungal infections

More information: The article is available free online at www.liebertpub.com/mdr

Related Stories

Resistant gut bacteria will not go away by themselves

Jun 19, 2007

E. coli bacteria that have developed resistance to antibiotics will probably still be around even if we stop using antibiotics, as these strains have the same good chance as other bacteria of continuing to colonise the gut, ...

UTIs becoming harder to treat

May 17, 2010

Genes that make bacteria resistant to antibiotics can be transferred between humans and other animals, say researchers writing in this month's issue of the Journal of Medical Microbiology. The findings will help health expert ...

The structure of resistance

Feb 22, 2008

A team of scientists from the University Paris Descartes has solved the structure of two proteins that allow bacteria to gain resistance to multiple types of antibiotics, according to a report in EMBO reports this month. ...

Recommended for you

Waiting to harvest after a rain enhances food safety

19 hours ago

To protect consumers from foodborne illness, produce farmers should wait 24 hours after a rain or irrigating their fields to harvest crops, according to new research published in the journal Applied and Environmental Microbiology.

A triangular protein pump

23 hours ago

Ludwig Maximilian University of Munich researchers have elucidated the structure of a molecular machine with an atypical triangular shape that is involved in peroxisome biogenesis, and characterized its conformation ...

Researchers discover new mechanism of DNA repair

Jul 03, 2015

The DNA molecule is chemically unstable giving rise to DNA lesions of different nature. That is why DNA damage detection, signaling and repair, collectively known as the DNA damage response, are needed.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.