Distribution of genomic regions homologous to the PAIs from enteropathogenic bacteria. According to each PAI, left bar denotes the number of genomes containing at least one cPAI. Right hatched bar delineates the number of genomes containing at least one PAI-like region. Different colors represent the number of genomes of different taxon – Enterobacteriales (black), Proteobacteria except Enterobacteriales (red), and phylums except Proteobacteria (green). The demonstrated PAIs are PAI I,II,III536 in uropathogenic E. coli 536, PAI IICFT073 in uropathogenic E. coli CFT073, LEE in enterohemorrhagic E. coli O157, SPI-2 in S. typhimurium, SHI-2 and SRL in S. flexneri, HPI in Y. enterocolitica, and TTSS locus in Photorhabdus lumniescens.