Table 2.
Spontaneous reversion frequencies of episomal lacZ alleles in various polB backgrounds
| Reversion event | Lac+ revertants/108 cells plated*
|
|||
|---|---|---|---|---|
|
dnaE+
|
dnaE915
|
|||
| polBex1 | polB+ | polBex1 | polB+ | |
| Base substitutions | ||||
| G·C → A·T | 64.5 ± 2.1 | 14 ± 2.6 | 22.2 ± 0.3 | 2.8 ± 0.8 |
| G·C → C·G | 0.5 ± 0.1 | 0.02 ± 0.02 | 7 ± 1.2 | 0.2 ± 0.1 |
| G·C → T·A | 1.7 ± 0.3 | 0.6 ± 0.2 | 6.2 ± 0.7 | 0.3 ± 0.1 |
| A·T → T·A | 0.8 ± 0.2 | 0.2 ± 0.1 | 2.1 ± 0.3 | 0.2 ± 0.1 |
| A·T → G·C | 20.3 ± 2.8 | 13.3 ± 1.9 | 2.8 ± 0.3 | 17.0 ± 2.1 |
| A·T → C·G | ND | ND | ND | ND |
| Frameshifts | ||||
| +1 A | 175 ± 6 | 35 ± 3 | 1497 ± 71 | 96 ± 3 |
| −1 A | 663 ± 76 | 564 ± 50 | 1114 ± 68 | 258 ± 19 |
| −1 G | 4196 ± 177 | 2074 ± 305 | 7687 ± 187 | 4428 ± 79 |
| +1 G | 7241 ± 245 | 6952 ± 342 | 3092 ± 96 | 3287 ± 174 |
| −2 (CG) | 638 ± 25 | 846 ± 53 | 530 ± 37 | 605 ± 34 |
All strains were mutL::Tn5. ND, not detected.
*
Average of five or more independent isolates ± SEM.