FIGURE 2.

Presence of cysteine-degrading genes across the human gut microbiome. Important genera of the human gut microbiome and the presence/absence of cysteine-degrading genes in each clade. The taxonomic tree is obtained from the Unified Human Gastrointestinal Genome collection (UHGG) (Almeida et al., 2020) which is built on the Genome Taxonomy Database (GTDB) (Chaumeil et al., 2020). Phyla names are annotated on the left side. Phyla followed by a capital letter, e.g., Desulfobacterota (A), indicate a novel phyla classified by the GTDB-tk (Chaumeil et al., 2020). The bar chart in the center of the figure represents the number of species contained under each genus or higher clade. The color of the circles on the right indicates whether the gene is a primary (green), secondary (yellow) or erroneous (red) producer of H₂S (Supplementary Note 1). The circles on the right side represent the number of species in each clade that contain hits to the genes specified. Nodes collapsed at levels higher than genus are because all genomes in that clade contain the same combination of genes reported in the grid on the right. The full, untruncated version of this figure is available in the supplementary information (Supplementary Figure 2).