Gordon views the human gut as "a bioreactor programmed with at least 800 different species of bacteria." "Fortunately, these microbes endow us with key metabolic functions that we have not had to evolve on our own," Gordon says.
He and his colleagues have used mouse models of the human gut ecosystem to show that intestinal bacteria allow calories to be harvested from otherwise indigestible components of the diet, such as polysaccharides. These microbes also regulate the amount of extracted energy that is stored in fat cells. The implication of these findings is that variations in the composition of gut microbial communities among different people may be an important factor that influences predisposition to obesity and obesity-related disorders such as diabetes and heart disease.
Unfortunately, comprehensive analysis of the composition and functions of these microbial communities, in health and in disease, has been hampered because the majority of gut bacteria are difficult or impossible to grow and study outside of the intestine. With the support provided by the Keck Foundation, the researchers will create new techniques for harvesting microbial communities along the length of the intestine and sequencing the genomes of new species, without having to culture them in test tubes.
They are also developing new computational methods for mining genome sequence data so that bacterial species can be more rapidly and accurately classified. A large publicly accessible database will be established that provides detailed molecular information about the gut ecosystem for researchers.
A second aspect of the project aims to directly identify the products of bacterial metabolism in the intestine. The goal is to characterize previously unknown chemical compounds that play important roles in regulating the properties
Source:Washington University in St. Louis