25 Aug 2020

Stronger together in the microbiome: how gut microbes feed each other to overcome dietary deficiencies, change host behavior, and improve reproduction

To study how the microbiome affects their host behavior, a group of researchers at the Champalimaud Centre for the Unknown, in Lisbon – Portugal, used the fruit fly combined with high-tech tools to show that two gut bacteria establish a metabolic cross-feeding that enables them to grow in diets that lack the nutrients that are essential for their growth and to allow them to change host decision making and reproduction. Results reveal a mechanism through which the right combination of bacteria can lead to microbiome resiliency to dietary perturbations and changes in brain function.

Stronger together in the microbiome: how gut microbes feed each other to overcome dietary deficiencies, change host behavior, and improve reproduction

A balanced intake of essential amino acids is crucial to ensure the well-being and health of all animals. The essential amino acids are the building blocks of proteins but they also influence how much offspring animals produce, and what animals decide to eat.

Gut bacteria use a metabolic cross-feeding to overcome dietary deficiencies, and to change the host behavior and reproductive output
Image: Gil Costa

Intriguingly, researchers at the Champalimaud Centre for the Unknown had previously shown that the microbiome plays an important role in dictating how amino acids affect the brain. What was most puzzling was that bacteria could only affect the decisions of the animal when they were present in specific combinations. It is widely known that the microbiome often contains many different species of bacteria but why different types of bacteria are needed to influence brain function and alter host physiology remains a mystery. This is the puzzle Carlos Ribeiro and his team at the Champalimaud Centre for the Unknown set out to tackle: . “To study how bacteria affect their host physiology is a daunting task in organisms with very complex microbiomes. This is where the fly and its less complex microbiome emerges as a powerful tool. It allows us to precisely dissect the mechanisms used by the microbiota to change the host’s feeding decisions.”, points out Sílvia Henriques, post-doctoral researcher and author of this study published today (August 25th) in the journal Nature Communications.

Read the full story here.