Fig. 4

The pan-genome distribution among 2324 E. coli genomes. The pan-genome distribution of 2324 E. coli genomes as 1000 bp genomic segments. The majority (29.7Mbp) of the 37.44 Mbp pan-genome is present in fewer than 100 genomes, with the core genome size (present in at least 2300 genomes) observed to be 1.86Mbp. Only 5.84Mbp of the pan-genome was found in greater than 100 genomes, but fewer than 2300 genomes. Of these 2324 genomes, only 1641 had metadata beyond the name of the strain