TABLE 1

Phylogenies, chromosomal virulence loci, and corresponding phenotypes of Czech and German SF EHEC O157:H strains

StrainReferenceDisease or origin, country of originaSerotype [fliC type]ST (CC)bstx locus (or loci)Presence of chromosomal virulence locusPhenotypeg
cdtVceaeefa1dlpfAO157 OI-141lpfAO157 OI-154ihatereurefStx type (LA)Stx titer (Vero cells)CdtV titer (CHO cells)Growth on CT-SMACSF/GUD phenotype
258/983HUS, CRO157:H [H7]11 (11)stx2a+γ+++2a1:1,0241:8+/+
269/983D, CRO157:H [H7]11 (11)stx2a+γ+++2a1:5121:8+/+
493/8970HUS, GO157:H [H7]11 (11)stx2a+γ+++2a1:5121:4+/+
3072/9630, 37HUS, GO157:H [H7]11 (11)stx2a+γ+++2a1:1,0241:4+/+
EDL93371Outbreak, USAO157:H7 [H7]11 (11)stx1a + stx2aγ+++++1a + 2a1:2,048<1:2+−/−
Sakai72Outbreak, JO157:H7 [H7]11 (11)stx1a + stx2aγ+++++1a + 2a1:2,048<1:2+−/−
  • a HUS, hemolytic-uremic syndrome; D, diarrhea; G, Germany; CR, Czech Republic; USA, United States; J, Japan.

  • b ST, sequence type; CC, clonal complex.

  • c +, all components of the cdtV operon (cdtV-A, cdtV-B, and cdtV-C) were present; −, all these genes were absent.

  • d +, complete efa1 was detected by PCR; −, only the 5′ fragment of efa1 was present.

  • e +, all genes of the ter operon (terZABCDEF) were present; −, all these genes were absent.

  • f +, all genes of the ure operon (ureABCDEFG) were present; −, all these genes were absent.

  • g Shiga toxin (Stx) and cytolethal distending toxin V (CdtV) titers are the highest dilutions of culture supernatants that caused typical morphological effects in 50% of cells. LA, latex agglutination assay; CHO, Chinese hamster ovary cells; CT-SMAC, cefixime-tellurite sorbitol MacConkey agar; SF, sorbitol fermentation; GUD, β-d-glucuronidase.