Gut bugs help battle invading E. coli

Washington, May 11 (IANS) From tiny villages in the developing world to suburban US kitchens, dangerous strains of E. coli bacteria sicken millions of people each year and kill untold numbers of children. But now, a new research shows that the bugs living in our gut combat invading E. coli and help our bodies fend them off.

The research done from the University of Michigan Health System, shows how the bugs living in our gut could help battle the invading E. coli.

That the invaders depend on certain genes to gain a temporary upper hand in that battle -- just long enough to reproduce and expel their offspring from the body so they can find a new host, the journal Science reported.

The findings point to potential ways to prevent or treat infections by enterohemorrhagic or enteropathogenic E. coli. Those are the types that can lurk in undercooked ground beef, unpasteurized milk, untreated drinking water, and contaminated produce - and that can cause diarrhoea and other symptoms that sicken adults and can kill vulnerable children.

"More than 1,000 species of bacteria live in our guts, in a symbiotic population called the microbiota," said Gabriel Nunez, the Michigan pathologist who led the research team, according to a university statement.

"These results show that these (gut) bacteria, also called commensals, compete with pathogens (disease-causing bacteria) in a previously unappreciated way - and that the pathogens use a specific set of genes to temporarily outcompete commensals before leaving the body. Understanding this gives us potential targets for prevention and treatment," said Nunez.

For instance, since the research shows that harmful bacteria compete with commensal bacteria for certain nutrients that they need to survive, selectively removing some nutrients and boosting others might help. So might a more targeted use of antibiotics when treating patients who are battling an E. coli infection.

Nunez and study co-author Nobuhiko Kamada, postdoctoral fellow, made the findings by studying mice that they infected with C. rodentium - the rodent equivalent of harmful E. coli. The study included specially bred germ-free mice that lacked all the "good" gut bacteria that normal mice and humans harbour.