Researchers from a host of countries have so far isolated 10 variants of the E.coli 0104:H4 that killed 50 and sickened 4,000. The outbreak was centred in northern Germany but affected 15 other countries in Europe and North America.
The sequencing will provide key information for food safety experts on how the bug was able to infiltrate the global food chain, said the Society for General Microbiology.
It will also give clues as to how the outbreak arose.
The process to sequence the bacteria kicked off in China in June. The initial sequence was made available to the international community as a ‘crowd sourcing’ project – which led to scientists identifying the organism’s main disease-causing genes.
This could help food safety authorities avoid future similar outbreaks, said Dr Lisa Crossman from the UK’s Genome Analysis Centre (TGAC), which has taken part in the research.
“We have found that the E.coli strain responsible for the outbreak carries a very high number of genes known to be involved in disease,” she said. “These include genes that influence the bacterium’s ability to attach to surfaces and survival genes that increase tolerance to high acidity, low oxygen, UV light and antibiotics.”
The E.coli 0104:H4 outbreak strain has gained the ability to make a toxin from a bacterial virus source which makes it more dangerous, said Crossman.
Foothold in global food chain
The partnership approach means scientists have established the outbreak strain is most closely related to one isolated in Central Africa some years ago.
Institutions from around the world have now isolated 10 variants of the E.coli 0104:H4.
“These variants represent a tremendous resource to examine the bug in a new, rapid and exciting way,” said the scientist. “By studying the genetics factors involved in the survival of this bacterium on surfaces, we hope to get an angle on how this organism has been able to get a foothold in the global food chain.”