The dispersin-encoding gene (aap) is not restricted to enteroaggregative Escherichia coli

The presence of the enteroaggregative Escherichia coli (EAEC) virulence genes aatA, aap, and aggR was assayed in strains of different diarrheagenic E. coli pathotypes and nonpathogenic E. coli. The dispersin-encoding gene (aap) was detected in EAEC, diffusely adherent E. coli, and nonpathogenic E. coli, demonstrating that molecular diagnostics of EAEC based on aap detection may identify non-EAEC strains.