Fig. 3

Metabolomic signatures of feces from GF, PTS and LTS mice. Partial least squares discriminant analysis (PLS-DA) scores plots of fecal metabolites from GF and PTS mice (a) from GF and LTS mice (b) and from PTS and LTS mice (c). There are 30 samples for GF, from 3 sampling days and 2 cages, n = 5 per cage. There are 20 samples each for PTS and LTS, from 4 sampling days and one cage. d Enrichment of metabolic pathways and pathway analysis of t-test significant upregulated metabolites using pathway dataset and pathway analysis of LTS compared to PTS. e Enrichment and pathway analysis of t-test significant downregulated metabolites using pathway dataset and pathway analysis of LTS compared to PTS. f Metabolic pathway significance plotted against pathway impact of metabolites from PTS and LTS mice. The larger the diameter of the symbols, the greater the impact. g Heat map of metabolites illustrating changes in the metabolomic profiles of five GF mice after LTS and PTS gavage. Note the remarkable wide-ranging changes when GF mice were gavaged with bacteria, and the more specific changes between PTS and LTS mice. The top 10 metabolites selected on the basis of VIP scores after comparative analysis of feces from PTS and LTS (h) GF and PTS (i) and of GF and LTS (j) mice. The ordinate represents the VIP scores of metabolites regardless of ionization mode, and of up or down regulation (Supplemental Table 3A to C). If both positive and negative ionization modes of a single metabolite had high VIP scores, only the higher VIP score was used