Metabolic pathway analysis of the murine fecal metaproteome. Top: distribution of the identified proteins belonging to the six main microbial kingdoms/phyla into metabolic pathways using iPATH. The upper legend explains the correspondence between colors and taxa. Bottom: detail of the Wood-Ljungdahl pathway (left) and of the dissimilatory sulfate reduction pathway (right). The proteins identified in this study are in bold type and their corresponding overall PSMs in brackets, while the adjacent text in italic illustrates the corresponding taxonomic assignments based on the LCA approach (phylum/kingdom-related color according to the upper legend) and listed according to the number of PSMs. Complete details are given in Additional file 7: Table S6. Abbreviations: ADP adenosine-diphosphate, APS adenosine-5’-phosphosulfate, THF tetrahydrofolate.