TABLE 2.
Presence of toxB sequences in EHEC strains, listed by serogroup
| Serogroup | No. of strains | Results ofa: |
||||
|---|---|---|---|---|---|---|
| PCR with toxB primer pair |
Hybridization with toxB probeb |
|||||
| A | B | C | D | E | ||
| O18 | 2 | − | − | − | − | − |
| O26 | 6 | + | + | + | 5.8 | 2.5 |
| O26 | 2 | + | + | + | − | 2.5 |
| O26 | 1 | + | + | − | 5.8 | 2.5 |
| O26 | 1 | + | + | − | 5.8 | − |
| O26 | 1 | + | − | + | − | − |
| O26 | 1 | − | − | − | − | − |
| O45 | 2 | − | − | − | − | − |
| O75 | 1 | − | − | − | − | − |
| O86 | 1 | − | − | − | − | − |
| O103 | 3 | − | − | − | − | − |
| O111 | 2 | + | − | − | − | − |
| O111 | 6 | − | − | − | − | − |
| O118 | 1 | + | + | + | 5.8 | 2.5 |
| O118 | 2 | − | − | − | − | − |
| O121 | 1 | + | + | + | − | 2.5 |
| O123 | 1 | + | + | + | 5.8 | 2.5 |
| O128 | 1 | − | − | − | − | − |
| O145 | 1 | + | + | + | − | 2.5 |
| O152 | 1 | − | − | − | − | − |
| O157 | 23 | + | + | + | 6.1 | 3.2 |
a
Primer pairs used for PCR amplifications (A, B, and C) and probes used for Southern hybridizations (D and E) are defined in the legend for Fig. 1.
b
The numbers are the sizes (in kilobases) of the DNA fragments hybridizing with the probe.