A zoomed heatmap of the amino acid frequency found in the deduced proteomes of all 145 genomes. A fragment of the heatmap is shown, presenting the cluster in which all but two Negativicutes are found. The remaining two, both Dialister microaerophilus genomes, are positioned elsewhere in the tree, closest to Clostridium cellulolyticum (not shown in this zoom). The color scale indicates highly underrepresented (orange) to highly overrepresented amino acid frequency (magentum). The full figure is available as supplementary information.