Length distributions of rRNA genes encoded in CPR and non-CPR genomes. (A–D) Density distributions of the whole-length 16S, 23S, and 5S rRNA genes and the total combined lengths of these three genes. Each horizontal axis is limited to the range in which the main peak occurs, and a few genes beyond this limit (A: 5.7%; B: 3.0%; C: 0.3%; and D: 1.5% of the total data) were omitted from the figures. (E–H) Density distributions of the 5S, 16S, and 23S rRNA gene lengths, excluding the insertion sequences, and their combined length for each genome. The numbers of data were: 16S rRNA genes (CPR bacteria, n = 375; symbiotic non-CPR bacteria, n = 167; free-living non-CPR bacteria, n = 1494), 23S rRNA genes (CPR bacteria, n = 347; symbiotic non-CPR bacteria, n = 167; free-living non-CPR bacteria, n = 1494), 5S rRNA genes (CPR bacteria, n = 630; symbiotic non-CPR bacteria, n = 167; free-living non-CPR bacteria, n = 1494), and the three genes combined (CPR bacteria, n = 240; symbiotic non-CPR bacteria, n = 167; free-living non-CPR bacteria, n = 1494). Density curves are colored according to group (CPR, light red; symbiotic non-CPR, light gray; free-living non-CPR, light blue).
