The cyanobacterial core and pan-genome.

<p>(A) The distribution of CLOGs as a function of the number of assigned strains. (B) The size of the pan-genome estimated for an increasing number of strains. The blue line indicates the mean size of the pan-genome, error bars indicate the standard deviation of 10⁴ randomly sampled subsets of strains. The red line shows a least squares fit of the power law <i>p</i> ∼ <i>N</i>^<i>g</i> (Heaps’ law), with <i>p</i> denoting the size of pan-genome and <i>N</i> the number of genomes. The estimated exponent <i>g</i> = 0.62 indicates an open pan-genome. (C) The size of the cyanobacterial core-genome estimated for an increasing number of strains. The blue line indicates the mean size of the core-genome whereas error bars indicate the standard deviation of 10⁴ randomly sampled subsets of strains. The estimates of pan- and core-genome do not include genomes of <i>E. coli</i> and <i>Cyanobacterium</i> UCYN-A.