Potential for colonization of O111:H25 atypical enteropathogenic E. coli.

Using clonal phylogenetic methods, it has been demonstrated that O111:H25 atypical enteropathogenic E. coli (aEPEC) strains belong to distinct clones, suggesting the possibility that their ability to interact with different hosts and abiotic surfaces can vary from one clone to another. Accordingly, the ability of O111:H25 aEPEC strains derived from human, cat and dogs to adhere to epithelial cells has been investigated, along with their ability to interact with macrophages and to form biofilms on polystyrene, a polymer used to make biomedical devices.

Atypical enteropathogenic Escherichia coli strains form biofilm on abiotic surfaces regardless of their adherence pattern on cultured epithelial cells.

The aim of this study was to determine the capacity of biofilm formation of atypical enteropathogenic Escherichia coli (aEPEC) strains on abiotic and biotic surfaces. Ninety-one aEPEC strains, isolated from feces of children with diarrhea, were analyzed by the crystal violet (CV) assay on an abiotic surface after 24 h of incubation. aEPEC strains representing each HEp-2 cell type of adherence were analyzed after 24 h and 6, 12, and 18 days of incubation at 37°C on abiotic and cell surfaces by CFU/cm(2) counting and confocal laser scanning microscopy (CLSM).