School of Medicine

Beneficial gut microbe has surprising metabolic capabilities

Researchers at WashU Medicine have discovered a gut bacterial enzyme with previously unknown metabolic capabilities. Shown are the structures of the bacterial version of the enzyme, called FAAH (left), and the human version (right). Prior to this study, only the human version of the enzyme was known. The microbe that makes the bacterial version is associated with the growth benefits of a therapeutic food to treat malnutrition in children. (Image: Jiye Cheng)

To address childhood malnutrition — which affects 200 million children globally — researchers at Washington University School of Medicine in St. Louis developed a therapeutic food that nourishes the collections of beneficial microbes that reside in the gut, and improves children’s growth and other measures of their health. But to understand just how this food therapy works, the research team led by physician-scientist Jeffrey I. Gordon, MD, zeroed in on how the children’s gut microbiomes respond to the therapy.

In their latest study, the researchers discovered potentially far-reaching effects of a particular gut bacterium that was linked to better growth in Bangladeshi children receiving a therapeutic food designed to nurture healthy gut microbes. This microbiota-directed therapeutic food is called MDCF-2. A strain of the bacterium harbored in the children’s gut microbial communities possessed a previously unknown gene capable of producing and metabolizing key molecules involved in regulating many important functions ranging from appetite, immune responses, neuronal function, and the ability of pathogenic bacteria to produce disease.

The results are published Oct. 25 in the journal Science.

“As we apply new therapies to treat childhood malnutrition by repairing their gut microbiomes, we have an opportunity to study the inner workings of our microbial partners,” said Gordon, the Dr. Robert J. Glaser Distinguished University Professor and director of the Edison Family Center for Genome Sciences & Systems Biology at WashU Medicine. “We are discovering how the gut microbes affect different aspects of our physiology. This study shows that gut microbes are master biochemists that possess metabolic capabilities that we have been unaware of.”

A better understanding of the effects our gut microbes have on our bodies could lead to new strategies to maintain human health and help guide the development of therapeutics for a wide variety of diseases beyond malnutrition, according to the researchers.

In two randomized controlled clinical trials of the therapeutic food in malnourished Bangladeshi children, the researchers identified a collection of microbes whose abundances and expressed functions correlated with the improved growth of study participants. One of these beneficial organisms is a bacterium called Faecalibacterium prausnitzii.

Read more at The Source.