TABLE 2.
Frequency of transformation of C. coli strains to nalidixic acid resistance
| Recipient straina | STb | IVSc | Susceptibility to erythromycin (10 μg/ml) | Mean transformation frequencyd |
|---|---|---|---|---|
| 8266 | 1101 | Present | Resistant | 1.82 × 10−4 |
| 6017 | 1150† | Hybrid | Susceptible | 2.30 × 10−5 |
| 6979 | 1150† | Absent | Susceptible | 4.88 × 10−4 |
| 7755 | 1150† | Absent | Susceptible | 3.02 × 10−6 |
| 6667 | 1161† | Absent | Susceptible | 8.73 × 10−6 |
| 7474 | 1161† | Absent | Susceptible | 1.98 × 10−4 |
| 7080 | 1175 | Present | Susceptible | 7.19 × 10−6 |
a
Recipient strains were all susceptible to nalidixic acid. The donor strain was 6818 (ST-1101; IVS present, resistant to both erythromycin and nalidixic acid).
b
†, MLST cluster II isolate with the C. jejuni aspA103 allele.
c
Present, IVS present in all three 23S rRNA genes; absent, IVS absent from all three 23S rRNA genes; hybrid, IVS present in at least one, but not all three, 23S rRNA genes.
d
Mean transformation frequencies were calculated from values derived from at least two independent experiments.