FIG. 1.

Genetic organization of the proA-yagU region of E. coli. The gene organization and content of the proA-yagU region of genome-sequenced E. coli strains is depicted. The vat gene is found in the same position and orientation in all the extraintestinal pathogens but is absent from the intestinal pathogenic isolates. With the exception of several genes conserved among EAEC 042, EHEC EDL933, and E. coli K12, the genetic content of each island is remarkably distinct, indicating that this region is a hotspot for recombination. Loci shared between pathogenicity islands are highlighted in the same color. Loci previously implicated in pathogenesis are shaded and labeled. UPEC, uropathogenic E. coli; NMEC, neonatal meningitis E. coli; EPEC, enteropathogenic E. coli; EHEC, enterohaemorrhagic E. coli; EAEC, enteroaggregative E. coli.