Soil bacteria provide promising E.coli treatment

A successful treatment for one of the most serious forms of the E.coli bacterium has been found in a study involving the University of Strathclyde.

Treatment for the severe stomach bug can be difficult, as antibiotics are known to make the disease worse by releasing a potent toxin into the infected person’s gut.

A new study involving Strathclyde, and led at the University of Glasgow, has found a product made by natural soil-living bacteria called Streptomyces that can successfully treat the E. coli O157 bacterium – without producing any serious side effects.

The new study, published in the journal Infection and Immunity, found that Aurodox, a compound first discovered in 1973 but found to be poorly active as a true antibiotic, was able to block E. coli O157 infections.

Scotland has one of the highest incidences of E. coli O157 in the world and almost half of O157 cases in Scotland are in children under 16 years of age.

Rebecca McHugh, a joint PhD student at Strathclyde and Glasgow and a partner in the research, said: “We have a huge problem with E.coli O157 and it can be present in more types of food than many people might think. 

“We were able to show that the compound was capable of preventing E.coli O157 from attaching to the cells of the gut. You can’t treat E.coli O157 with traditional antibiotics, as it leads to over-production of the toxins, which lead to the serious complications in these infections.

“This compound is also produced in the soil. In my PhD, I’ll be looking to understand how we can over-produce the compound from the soil bacteria, in order to use it more effectively.”  

Paul Hoskisson, Professor of Molecular Microbiology at Strathclyde and a participant in the research, said: “This study shows that there are still useful compounds to be discovered from soil bacteria, such as Streptomyces and that we can also repurpose existing, forgotten- about compounds for new uses. This will be important for our continued fight against antimicrobial resistant infections.

“This work also shows a new strategy to combat infections, by neutralising the weapons the disease-causing bacteria use to make us ill, rather than killing them, which may complicate the illness.

“We are now turning our attentions to the Aurodox producing bacterium to try and fully understand how it is made and how we can enhance production.”

The Aurodox compound was able to reduce the ability of E. coli O157 to bind to human cells and, unlike traditional antibiotics, did not cause the release of potent toxins. The researchers believe that this compound could be used as a promising future treatment of E. coli O157 infections.

E. coli O157 causes diarrhoea, stomach cramps and occasionally fever and its symptoms may last up to 14 days; however, the bacteria can still be present for longer than this. Some people who are infected show no symptoms, while others go on to develop very serious complications, which can sometimes be fatal. Young children are at higher risk of E. coli infection and, along with older adults, are at greater risk of serious complications.