TABLE 1.
Summary of analysis results of STEC strains isolated from produce
Strain | Serotypea | Source | Results of analysis |
|||||
---|---|---|---|---|---|---|---|---|
PCRb | Stx2c | EhxAd | saae | subABf | sabg | |||
09-00002 | NA | Spinach | stx2, ehxA | + | + | + | + | NAh |
09-00009 | O172:H2 | Spinach | stx2 | − | NA | − | − | NA |
09-00024 | O116:H21 | Spinach | stx2, ehxA | + | + | + | + | NA |
09-00025 | O116:H21 | Spinachi | stx2, ehxA | + | + | + | + | NA |
09-00026 | O116:H21 | Spinachi | stx2 | + | NA | − | − | NA |
09-00027 | O113:H? | Spinach | stx2, ehxA | + | + | + | + | − |
09-00028 | O8:H− | Spinach | stx2, ehxA | − | Weak + | − | − | NA |
09-00029 | O11:H15 | Spinach | stx2? | − | NA | − | − | NA |
09-00031 | O−:H19 | Spinach | stx2, ehxA | + | + | + | + | NA |
09-00039 | O168:H8 | Spinach | stx2, ehxA | + | − | − | − | NA |
09-00043 | O−:H21 | Spinach | stx2 | − | NA | − | − | NA |
09-00047 | O113:H21 | Spinach | stx2, ehxA | + | + | + | + | − |
09-00049 | O168:H− | Lettuce | stx2, ehxA | + | − | − | − | NA |
O and H serotyping results from the E. coli Reference Center, Penn State University.
Various PCRs were used to test for stx1 and stx2, ehxA (enterohemolysin), γ-eae, and other eae alleles, and for O antigen genes for O157, O26, O111, O121, O145, and O103 serotypes.
Serological analysis was done to test for Stx2 using VTEC-RPLA (Denka Seiken, Japan).
Enterohemolysis was done on blood agar plates with Ca2+ to test for EhxA.
PCR was used to test for the Saa gene.
PCR was used to test for the subtilase cytotoxin genes.
PCR was used to test for the gene encoding the STEC autotransporter protein.
NA, not applicable.
Organic product.