Sugar Helping Profs Map New Ground Against Deadly Bug

September 17, 2007 - News Release

Sugar may help the medicine go down, but what about a medicine that targets sugar to "take down" disease-causing bacteria?

Two University of Guelph researchers are taking this novel route to tackling Clostridium difficile in hopes of eventually developing a safe, effective vaccine against a bug that has sickened and killed people in hospitals and nursing homes across Canada and has threatened various animal species.

Professors Mario Monteiro of Guelph's Department of Chemistry and Scott Weese of the Department of Pathogiology hope their collaborative studies will ultimately lead to a carbohydrate-based vaccine for both people and animals.

No vaccine currently exists for C. difficile, a major cause of diarrhea, particularly among older people in hospitals and nursing homes. Most people are infected in institutions where commonly used antibiotics kill “good” bacteria in the gut, allowing the problem bug to thrive.

There is also evidence that the bacteria also pose a general community health risk and a risk of food-borne disease, Weese said. Last year, he found evidence of C. difficile in ground and processed meats sold in Canada.

Meanwhile, Monteiro has mapped out the chemical structure of polysaccharides, or complex chains of sugars, on the surface of the bacteria.

Learning more about the polysaccharides may ultimately help in developing vaccines based on carbohydrates or carbohydrate-protein complexes, he said.

“They seem to express similar sugar structures, which will make it easier to develop a vaccine that would target different strains of the bacteria,” Monteiro said.

While it would take years to develop and test a vaccine for human use, it is possible, he said. New commercially available vaccines for pneumococcal and meningococcal diseases are also based on bacterial surface sugars.

Monteiro's also developing sugar-based vaccines against Campylobacter, which causes food poisoning when improperly cooked chicken is eaten, and Helicobacter pylori, a common gut microbe that can cause gastritis, ulcers and stomach cancer.

Prof. Mario Monteiro
Department of Chemistry
519 824-4120, Ext. 53447

Prof. Scott Weese
Department of Pathobiology
519 824-4120, Ext. 54064

For media questions, contact Communications and Public Affairs: Lori Bona Hunt, 519-824-4120, Ext. 53338, or Deirdre Healey, Ext. 56982.

University of Guelph
50 Stone Road East
Guelph, Ontario, N1G 2W1