DNA scan yields insights into Germany's E. coli bug

June 23, 2011

A strain of E. coli bacteria blamed for killing dozens of people in Germany is a genetic mix whose ability to stick to intestinal walls may have made it so lethal, a study in The Lancet said on Wednesday.

A team led by Helge Karch, a professor at the University of Muenster, said the germ O104:H4 was a rare kind that in essence was a "clone" of a strain first detected in a young patient in Germany in 2001.

Its genes for virulence come from two strains that have combined, they said.

One strain, called enterohaemorragic E. coli (EHEC), releases poisons called Shiga toxins.

The other, called enteroaggregative E. coli (EAEC), adheres in a "stacked brick" fashion to epithelial cells which constitute the intestinal lining.

Sequencing by gene labs in the United States and China last month also spoke of a hybrid EHEC-EAEC strain.

The new study, delving into a catalogue of bacteria, said the mix had been around, albeit in a rare form, for a decade.

What is different from the 2001 germ, it added, are genes that make it resistant to members of a broad class of antibiotics called beta-lactams.

The germ was resistant to all penicillins and cephalosporins, but susceptible to carbapenems.

This blending of traits could explain the exceptional virulence of the strain and suggests beta-lactams may have inadvertently made things worse by wiping out rivals to the , says the study.

Nearly a quarter of those infected in the outbreak have developed haemolytic uraemic syndrome (HUS), which includes kidney impairment, a breakdown of and lack of blood-clotting components called platelets.

"The enhanced adherence of this strain to intestinal epithelial cells might facilitate systemic absorption of Shiga toxin and could explain the of progression to HUS," the study suggested.

" might also play a part if beta-lactam drugs used to treat the infection suppressed competing microbiota."

As of June 20, there had been 39 recorded deaths, 810 cases of HUS and 2,684 non-HUS cases, entailing bloody diarrhoea, the paper said.

By comparison, most people with just EHEC infection recover completely, and usually fewer than 10 percent of them develop serious complications, including HUS.

Karch's team analysed the DNA from stool samples found in 80 patients with HUS that were submitted to the lab in Muenster between May 23 and June 2.

All of these samples were "clones," or copies, of the HUSEC041, an E. coli strain identified in 2001 in a child with HUS.

Explore further: Threat to United States from new European E. coli strain unclear

Related Stories

Threat to United States from new European E. coli strain unclear

June 14, 2011
(Medical Xpress) -- Over the centuries, many unexpected things have come to the United States from Germany and caught on -- lager beer, sauerkraut, bratwurst and the Volkswagen Beetle are a few that come to mind -- but don't ...

Antibodies successful in the treatment of the hemolytic-uremic syndrome from EHEC

May 31, 2011
In the online version of the New England Journal of Medicine, physicians and scientists in Heidelberg, Montreal, and Paris reported on the successful treatment of three young children who were suffering from a severe hemolytic-uremic ...

BGI sequences genome of the deadly E. coli in Germany and reveals new super-toxic strain

June 2, 2011
The recent outbreak of an E. coli infection in Germany has resulted in serious concerns about the potential appearance of a new deadly strain of bacteria. In response to this situation, and immediately after the reports of ...

Recommended for you

H7N9 influenza is both lethal and transmissible in animal model for flu

October 19, 2017
In 2013, an influenza virus that had never before been detected began circulating among poultry in China. It caused several waves of human infection and in late 2016, the number of people to become sick from the H7N9 virus ...

Flu simulations suggest pandemics more likely in spring, early summer

October 19, 2017
New statistical simulations suggest that Northern Hemisphere flu pandemics are most likely to emerge in late spring or early summer at the tail end of the normal flu season, according to a new study published in PLOS Computational ...

New insights into herpes virus could inform vaccine development

October 18, 2017
A team of scientists has discovered new insights into the mechanisms of Epstein-Barr virus (EBV) infection, as well as two antibodies that block the virus' entry into cells. The findings, published in Proceedings of the National ...

Pair of discoveries illuminate new paths to flu and anthrax treatments

October 17, 2017
Two recent studies led by biologists at the University of California San Diego have set the research groundwork for new avenues to treat influenza and anthrax poisoning.

Portable 3-D scanner assesses patients with elephantiasis

October 17, 2017
An estimated 120 million people worldwide are infected with lymphatic filariasis, a parasitic, mosquito-borne disease that can cause major swelling and deformity of the legs, a condition known as elephantiasis. Health-care ...

New tools to combat kidney fibrosis

October 16, 2017
Interstitial fibrosis – excessive tissue scarring – contributes to chronic kidney disease, which is increasing in prevalence in the United States.

0 comments

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.