Metabolism of carbohydrates by human gut microbiome species
Research project
financed by the swedish Research Council.
This project aims at identifying the proteins of human gut microbiome species that are responsible for sensing, transporting and metabolizing complex carbohydrates.
The interplay between the gut microbiome and the cells of our body is crucial for human health. The species of the microbiome not only consume nutrients from our diet, but help in food digestion, and are involved in neurological signaling and in the defense against pathogens. Complex carbohydrates (fibers) are key nutrients for the growth of these microorganisms, as humans can only digest starch, sucrose, and lactose, while other energy sources are generally digested and absorbed before they reach the colon. Microbiome species, on the other hand, can ferment a wide variety of carbohydrates, but we lack the knowledge of which proteins and species are involved in the metabolism of specific carbohydrates, what are their substrates, and which products are formed.
This project will use a proteomics-based approach to delineate how individual gut microbiome species sense, transport, and metabolize complex carbohydrates, and how these contribute to growth interactions between species. This will be achieved by measuring the response of the proteome to the presence of diet-related carbohydrates of different complexity in representative species of our microbiome. The expectation is that proteins involved in the metabolism of a specific carbohydrate will be altered in their abundance or biophysical properties. Combining these results with high-throughput growth measurements of bacterial communities, and follow-up mechanistic experiments in these non-model organisms will increase our understanding of the principles of how bacterial communities assemble, i.e., which species dominate in specific conditions, or how one species can suppress the growth of another.
Overall, this project provides the first steps towards restoring a healthy gut microbiome state through diet alterations.