Friday, June 3, 2011
DNA Sequencing Data Reveals New Hybrid E. coli Strain is Cause of German Outbreak
As a follow up to my posting regarding the recent E. coli outbreak in Europe, Life Technologies Corporation announced that preliminary data from DNA sequencing performed in cooperation with the University Hospital Muenster, Germany, on the Ion Personal Genome Machine (PGM™) strongly suggests that the bacterium at the root of the deadly outbreak in Germany is a new hybrid type of pathogenic E. coli strains.
The data obtained from the DNA sequencer shows the presence of genes typically found in two different types of E. coli: enteroaggregative E. coli (EAEC) and enterohemorrhagic E. coli (EHEC). These results, which are being confirmed by further data analysis on the Ion PGM™, may provide insight into this bacterium's aggressiveness and help prevent further outbreaks.
"The rapid whole genome sequencing results enabled us to discover within days a unique combination of virulence traits ... and makes this German outbreak clone a unique hybrid of different E. coli pathovars," said Dr. med. Alexander Mellmann, scientist at the German National Consulting Laboratory for Hemolytic Uremic Syndrome (HUS) at the Institute of Hygiene, University Hospital Muenster.
The data gathered at Life Technologies' laboratories in Darmstadt, Germany, will be used by scientists at the University Hospital Muenster, to develop better tests to positively identify the illness in people showing symptoms of the infection, which includes kidney failure and bloody diarrhea. For the first time since the outbreak, it is now possible to study in detail the basis for what makes this strain so aggressive.
Life Technologies' Simone Guenther, Ph.D., who carried out the sequencing work, said: "The severity of this outbreak meant that speed was of the essence. We were able to provide the data in record time to University Hospital Muenster. In previous outbreaks it would have taken much longer to reach this stage."
To prevent further spreading of the bacterium, Life Technologies began shipping its custom E. coli testing kits to European laboratories this week to screen contaminated food thought to be at the center of the outbreak that has killed 17 people and affected more than 1,000 in Europe.
The kits serve as a first line of defense to detect the presence of pathogenic E. coli. Secondary testing is then performed using more specific kits. Life Technologies will develop new customized kits specifically designed to detect the hybrid strain inGermany once the sequencing data has been fully analyzed in the next few days. The company can design custom assays in less than one week.
The kits shipped to Europe are part of a large offering of molecular tests developed by Life Technologies capable of accurately detecting most pathogens that are dangerous to humans. The Ion PGM™ is a DNA sequencing instrument featuring semiconductor technology that can complete a highly accurate sequence of DNA in just two hours. The DNA sample used for the sequencing work was collected from a patient with the illness.