Table 1.
Efficiency of transformation of various dnaA and rpoB mutants with wild-type λ plasmids (pKB2 and pCB104) at 30°C
| Host | Efficiency of transformation
|
|
|---|---|---|
| pKB2 | pCB104 | |
| dnaA+rpoB+ | 1 × 105 | 7 × 104 |
| dnaA46 rpoB+ | <1 × 101 | <1 × 101 |
| dnaA+ rpoB902 | 4 × 102 | 7 × 102 |
| dnaA46 rpoB902 | 6 × 104 | 5 × 104 |
| dnaA204 rpoB+ | <1 × 101 | <1 × 101 |
| dnaA204 rpoB902 | <1 × 101 | <1 × 101 |
| dnaA204 rpoB903 | 1 × 105 | 1 × 105 |
| dnaA508 rpoB+ | <1 × 101 | NT |
| dnaA508 rpoB902 | <1 × 101 | NT |
| dnaA508 rpoB904 | 6 × 104 | NT |
Efficiency of transformation is presented as number of transformants per 1 μg of plasmid DNA. NT denotes “not tested” due to the fact that strain CM2555 (dnaA508) and its derivatives are sensitive to chloramphenicol even when containing a plasmid bearing the cat gene (18), like pCB104.