Gut bacteria can battle autoimmune diseases

Bacteria that have evolved to help us digest the yeast that give beer and bread their bubbles could support the development of new treatments to help people fight off yeast infections and autoimmune diseases such as Crohn's disease.

The study by scientists from Newcastle University in the United Kingdom and the University of Michigan Medical School shows how microbes in humans digestive tract have learned to unravel the difficult to break down complex carbohydrates that make up the yeast cell wall.

Evolving over the 7,000 years that people have been eating fermented food and drink, the ability of a common gut bacterium called Bacteroides thetaiotomicron to degrade yeasts was almost exclusively found in the human gut.

The international research team stated that the discovery of this process could accelerate the development of prebiotic medicines to help people suffering from bowel problems and autoimmune diseases.

The new findings provide a better understanding of how the unique intestinal soup of bacteria, termed the microbiome, has the capacity to obtain nutrients from our highly varied diet. Their findings suggested that yeast has health benefits possibly by increasing the Bacteroides growth in the microbiome.

Involving an international team of scientists from the United Kingdom, Australia, Canada, United States and Belgium, the research has unraveled the mechanism by which B. thetaiotaomicron has learned to feast upon difficult to break down complex carbohydrates called yeast mannans.

Researchers believed this mechanism emanated from the ability of common gut bacteria to recycle chemically similar carbohydrates present on intestinal cells, which are constantly being shed and renewed to keep the intestinal lining healthy.

It had been hoped that the research could aid a better understanding of how to provide nutrients to specific organisms in the microbiome.

The study is published in Nature.