Despite not always representing changes in bacterial activity, variations in bacterial diversity in the human gut have been linked to various diseases. Enhanced understanding of how bacterial communities adapt and respond to their environment, such as the gut, requires methods that link bacterial identity to function. Researchers used a combination of bioorthogonal non-canonical amino acid tagging (BONCAT) and fluorescently activated cell sorting and sequencing (FACS-Seq) to discover the translationally active components of the gut microbiota. We next compared this unique technique to other bulk community activity and survivability metrics, such as relative nucleic acid concentration and membrane damage. About half of the gut microbiota are translationally active, and they are not unique from the rest of the community. For example, the bacteria with high nucleic acid concentrations make up half of the gut microbiota. Still, they were separated from the rest of the community and are associated with the damaged fraction. When the community was perturbed with xenobiotics that had previously been demonstrated to impact bacterial activity but not diversity, the physiological fractions responded more strongly than the overall community. BONCAT is an effective approach for probing the gut microbiota’s translationally active members, and when paired with FACS-Seq, it enables their identification. The bacteria with the highest nucleic acid content are not always the protein-producing bacteria in the community; therefore, more research is needed to understand better the link between nucleic acid concentration and bacterial metabolism in the human gut. Considering physiologically different subgroups of the gut microbiota instead of the entire community may be more revealing.

 

Link:www.tandfonline.com/doi/full/10.1080/19490976.2021.1903289