TABLE 5.
Detection of E. coli O157:H7 strain Tw04 in seeded samples
| Sample | Real-time PCR result with probe specific for:
|
Plate count | |
|---|---|---|---|
| O157 | stx2 | ||
| Plasmid | |||
| P1c | NDa | 6.9b | 7.1b |
| P2c | ND | 5.1 | 4.3 |
| Milk | |||
| M1d | 8.0 | 8.0 | 8.0 |
| M2d | 3.6 | 3.6 | 4.0 |
| Apple juice | |||
| A1e | 7.8 | 7.8 | 8.0 |
| A2e | 5.1 | 5.1 | 5.1 |
| Human feces | |||
| F1f | 6.7 | 6.7 | 7.0 |
| F2f | 4.9 | 4.9 | 5.1 |
a
ND, not detectable; stx2-specific probe has only the stx2 gene.
b
Log10 CFU/ml or log10 CFU/g of sample.
c
P1 and P2 were different concentrations of the plasmid in the imitated samples.
d
M1 and M2 were different cells of E. coli O157:H7 strain Tw04 in the imitated milk samples.
e
A1 and A2 were different cells of E. coli O157:H7 strain Tw04 in the imitated apple juice samples.
f
F1 and F2 were different cells of E. coli O157:H7 strain Tw04 in the imitated fecal samples.