Distinct binding properties of eaeA-negative verocytotoxin-producing XXXX of serotype O113:H21.

@entity1 @entity95 @entity6286 @entity281 @entity941 @entity8859 @entity526
Infection of @entity1 with verotoxin-producing @entity526 (VTEC) O113:H21 is associated with clinical features comparable to those associated with @entity281 with attaching and effacing VTEC strains including those of serotype O157:H7. We have shown previously that the adhesion phenotype of VTEC O157:H7 is influenced by the presence of a homolog of the chromosomal eaeA (for @entity526 attaching and effacing) gene. In contrast, by colony blot hybridization, VTEC O113:H21 is negative for the eaeA gene. Therefore, the aim of this study was to define the adhesion phenotype of VTEC O113:H21 strain CL-15 to both cultured epithelial cells (HEp-2) and @entity95 intestine in vivo. Under transmission electron microscopy, areas of microvillus effacement were observed in regions directly beneath the organism in @entity281 cells both in vitro and in vivo. However, F-actin adhesion pedestals on the host plasma membrane were absent. Failure of CL-15 to induce polymerization of actin was confirmed by using staining of F-actin with @entity941 -labeled @entity6286 . Under indirect immunofluorescence microscopy, @entity281 HEp-2 cells also failed to demonstrate the recruitment of another cytoskeletal element, @entity8859 , below foci of bacterial adhesion. In contrast, VTEC O157:H7 @entity281 of HEp-2 cells was associated with increased @entity8859 immunofluorescence. These findings suggest that bacterial factors distinct from those of EaeA are necessary for the adhesion phenotype of VTEC O113:H21.
