Australian researchers have modified probiotic microbes - “good” bacteria - that may be useful in preventing or treating travelers’ diarrhea, an all too common problem during trips to certain countries.

The microbes work against a type of E. coli bacteria that causes diarrhea by producing a chemical that is toxic to intestinal cells. The probiotic microbes carry a molecule that looks a lot like the toxin receptor found on intestinal cells. This mimicry causes the toxin to bind to the microbes instead of the intestinal cells.

Dr. James C. Paton, from the University of Adelaide and colleagues created the toxin-binding probiotic organisms.

Lab tests showed that these organisms could bind and neutralize a significant amount of enterotoxin, according to the report in the medical journal Gastroenterology. Moreover, treatment with these agents conferred significant intestinal protection in rabbits exposed to the toxin.

The results suggest that these probiotics could be a useful treatment for traveler’s diarrhea caused by E. coli, the researchers state.

“Significant safety issues will need to be addressed, but recombinant probiotics may afford sophisticated, novel biological therapies for a wide range of conditions in the years to come,” Dr. Claribel P. Taylor and Dr. J. Thomas LaMont, from Harvard Medical School in Boston, note in a related editorial.

SOURCE: Gastroenterology, May 2005.