Fig. 2.

Distribution of inteins does not correlate with genome size. (A) Distribution of the genome sizes and number of inteins in three bacterial clades. The clades are Proteobacteria (1016 species), Actinobacteria (527 species), and Cyanobacteria (130 species). (B) Distribution of the genome sizes and number of inteins in Euryarchaeota (190 species). For (A) and (B), vertical axis of plots represents distribution of the genome sizes (gray) and number of inteins (red and blue) in corresponding species on the horizontal axis. A representative species, genome size, and number of inteins are indicated for each group. No strong correlation between genome size and number of inteins was found, as indicated by correlation coefficient (r) for each group. Distribution of the coding sequences and frequencies of inteins (number of inteins per 1,000 coding sequences) is available in supplementary figure S2, Supplementary Material online. Correlation coefficients are provided in supplementary table S4, Supplementary Material online.