Fig. 2

Numbers of Orthologous Groups (OGs) present in a given fraction of chlamydial genomes as dependent on the number of sequentially added strains (saturation curves). The topmost curve shows the pan-genome size, the lowest curve shows the core genome size, and the remaining curves show OGs present in the given fractions of pan-genome (from top to bottom: any 2 genomes, 10%, 50% and 90% of genomes, respectively). Each dot represents a mean value obtained from 500 random permutations of the strain addition order. The jagged pattern is a consequence of the rounding procedure