Table 1.
Genetic markers of diarrheagenic Escherichia coli (DEC) pathotypes used in the classification of uropathogenic E. coli (UPEC) as a hybrid strain, and results obtained by virulence phenotypic tests.
| Strain | Pathotype Genetic Markers | Hybrid Classification | Phylogroup | Adherence Pattern c | Hemolysis d | Biofilm Formation/Medium e | |||
|---|---|---|---|---|---|---|---|---|---|
| DEC | ExPEC a | UPEC b | DMEM | LB | |||||
| HSP 60 | aggR | iucD, kpsMTII, papC | fyuA, chuA | UPEC/EAEC | D | NC | + (hlyA) | + | + |
| HSP 93 | aggR | afaBCIII, iucD, kpsMTII | fyuA | UPEC/EAEC | A | NC | + (hlyA) | − | + |
| HSP 117 | aggR | afaBCIII, iucD, kpsMTII | fyuA | UPEC/EAEC | A | NC | + (hlyA) | + | - |
| HSP 199 | aggR | - | - | UPEC/EAEC | B1 | AA | _ | − | + |
| HSP 215 | aggR | iucD, kpsMTII | fyuA | UPEC/EAEC | A | NC | + (hlyA) | + | + |
| HSP 414 | aggR | - | fyuA | UPEC/EAEC | B1 | AA | - | + | − |
| HSP 425 | aggR | afaBCIII, iucD, kpsMTII, papC | fyuA | UPEC/EAEC | A | NC | + (hlyA) | − | + |
| HSP 278 | eae | iucD | fyuA | UPEC/aEPEC | A | LAL | − | − | − |
| HSP 446 | eae | - | - | UPEC/aEPEC | B1 | LAL | − | − | − |
a Presence of at least two among five (pap, afa/dra, sfa, kpsMTII, and iut/iuc) genes determine the intrinsic virulence of the strains. b Simultaneous presence of vat, chuA, fyuA, and yfcV determines the uropathogenic potential of the strains. c As determined in HeLa cells. NC: non-characteristic aggregative adherence pattern; AA: aggregative adherence; LAL: localized adherence-like. d Assessed after incubation for 3 h, 6 h, and 24 h on washed blood agar containing 10 mM CaCl2; positive hemolytic strains detected in 3 h of incubation, except for HSP 425, which was detected after 6 h; hly+: presence of the hlyA gene. e DMEM, Dulbecco Minimal Essential Medium; LB: Lysogeny Broth; (+) biofilm formation; (−): lack of biofilm formation.