TABLE 5.
Integration frequencies of attPCTX, attPVGJ, and attPTLC elements in lacZ-dif1 reporter strains carrying different lexA alleles
| IMEXa | Host | Integration frequency, 10−7 (mean ± SD)b | No. of screened colonies |
|---|---|---|---|
| attPCTX | BS1 | 387 ± 273 | 1,160 |
| attPCTX | BS20 (ΔlexA) | 103 ± 65 | 310 |
| attPCTX | BD14a [lexA (Ind−)] | 960 ± 394 | 2,880 |
| attPVGJ | BS1 | 1,687 ± 716 | 5,060 |
| attPVGJ | BS20 (ΔlexA) | 2,110 ± 285 | 6,330 |
| attPVGJ | BD14a [lexA (Ind−)] | 250 ± 215 | 1,050 |
| attPTLC | BS1 | 340 ± 255 | 1,020 |
| attPTLC | BS20 (ΔlexA) | 1,543 ± 298 | 4,630 |
| attPTLC | BD14a [lexA (Ind−)] | 213 ± 81 | 640 |
a
IMEX, integrative mobile element exploiting Xer recombination.
b
Since all the plasmids carrying phage attachment sites were conditionally replicative, the integration frequency was estimated by counting numbers of white colonies on the selection plates and the total number of conjugants was obtained using a replicative plasmid carrying a similar genetic backbone without attP. The standard deviation was calculated from at least three independent experiments.