Fig. 8

An imbalance between mammalian and novel L. reuteri tryptophan metabolites is associated with enhanced autoimmunity. Serum was collected from mice fed a low- or high-tryptophan diet colonized with either the B6 or B6+L. reuteri microbiota following a 30-day EAE course and analyzed via UPLC-MS/MS as outlined in Fig. 4A, B. Partial least squares-discriminant analysis (PLS-DA) and volcano plots of differentially abundant metabolites, passing a threshold of |FoldChange|>1.5 and P<0.05 in low-tryptophan-fed mice (A, B) or high-tryptophan-fed mice (C, D). Heat maps of differentially abundant imidazoles in the serum of high-tryptophan-fed mice (E) or L. reuteri monoculture (F). Post hoc analysis using Fisher’s LSD of serum imidazoles (G–J), indoxyl glucuronide (L), and N-acetyl kynurenine (M) are represented as log-transformed and mean centered abundance plots