Table 3.
Vector switching frequencies of uvrD2allelesa
| Plasmid | Genotype | No. of Gmrtransformantsb | No. of Kanscolonies/no. of transformantsc |
|---|---|---|---|
| pAW26 | uvrD2 | 144 ± 43 | 58/64 |
| pAW27 | uvrD21-600 | 152 ± 10 | 51/64 |
| pAW28 | uvrD21-640 | 163 ± 50 | 55/64 |
| pAW29 | uvrD2(Q266R) | 8 ± 3 | 0/25 |
| pAW30 | uvrD2(E508A) | 90 ± 33 | 47/64 |
| pKP203 | 9 ± 3 | 0/28 |
a
The complemented ΔuvrD2strain was transformed with 500 ng of the indicated plasmid and with 300 ng pBS-Int. Colonies were selected for gentamicin resistance and then tested for kanamycin sensitivity.
b
Data shown are means ± standard deviations for gentamicin-resistant transformants obtained from three independent transformations from two separate experiments.
c
The number of kanamycin-sensitive colonies, indicating true complement replacement, is reported. Twelve kanamycin-sensitive colonies from each successful switch were verified by PCR and sequencing, and all showed that they were true complement replacements.