Fig. 1

Microbiota coding capacity for lactate utilizing genes in murine colitis model. A Schematic representation of D- and L-lactate metabolism. B Graphical representation of bacterial lactate utilizing enzymes. Lactate permease (LldP) facilitates the transport of both L- and D-lactate. The three membrane-bound respiratory lactate dehydrogenases, L-lactate dehydrogenase (LldD), D-lactate dehydrogenase (Dld), and the trimeric L-lactate dehydrogenase (YkgEFG/ LldDEFG/ LutABC), all convert pyruvate to lactate while contributing electrons to the quinone pool. Both fermentative L-lactate dehydrogenase (Ldh) and fermentative D-lactate dehydrogenase (LdhA) are cytoplasmic and catalyze conversion of pyruvate to L- and D-lactate, respectively. C Microbiota coding capacity for pathways involved in microbial lactate metabolism in a murine colitis model. Metagenomics was performed on a previously described dataset (Hughes et al., 2017; ENA accession number PRJEB15095). The cecal microbiota of mice treated with 3% DSS in their drinking water (colitis; black bars) were compared to mock-treated mice (gray bars). The normalized number of reads for lactate-related functions in the KEGG orthology database for each mouse is plotted. Columns represent mean and error bars represent standard deviation. Significance was determined using a 2-way ANOVA with Sidak’s multiple comparisons test. *, p<0.05; ***, p<0.001