Multiple amino acid sequence alignments of three selected ribosomal proteins that differ in length between CPR and non-CPR bacteria. (A–C) Distributions of the lengths of three ribosomal proteins (A: uL13; B: uS19; and C: uL1) with distinctly different lengths in CPR and non-CPR bacteria. Density curves for each protein length were calculated based on all sequences in the data set (CPR: light red; non-CPR: light blue). The total number of sequences is indicated in each panel. The length of each ribosomal protein in E. coli is indicated with a black inverted triangle. (D–F) Multiple amino acid sequence alignments of three ribosomal proteins corresponding to panels A–C (D: uL13; E: uS19; and F: uL1) are shown in the order based on a phylogenetic tree (Hug et al. 2016). Representative sequences were selected from each CPR and non-CPR group, and poorly aligned columns were removed (see Materials and Methods). The consensus residues in each column are highlighted in a blue gradient, according to the percentage identity calculated when gaps were ignored. The magnification and aspect ratio of each alignment panel have been adjusted for clarity. The scale bars of the alignment columns (amino acid lengths) are shown at the top right. The number of sequences included in the alignment is shown at the bottom. Panels on the left side of the alignment are colored according to the taxonomic group of each sequence (see Supplemental Fig. S1). MG: Microgenomates; Sa: Saccharibacteria; Pe: Peregrinibacteria; PB: Parcubacteria.
