Evaluating the effect of candidate prebiotics in the human gut microbiota by activity-based cell sorting and targeted isolation

To identify the metabolic activity of gut microbes on the single cell level, human fecal samples were incubated in the presence of two cellular activity markers L-Azidohomoalanine (AHA) and heavy water (D2O). In this project, we identified the metabolically-active taxa that utilized lactulose using single-cell stable isotope probing (SIP), Raman activated cell sorting (RACS) and biorthogonal non-canonical amino acid (BONCAT) fluorescence tagging combined with fluorescence activated cell sorting (FACS).