TABLE 1.
Plasmids described in the present study
| Plasmid | Relevant characteristics | OC (%)a | Mobilization efficiencyb | Reference or source |
|---|---|---|---|---|
| pC221 | pC221 wild type (inc4, chloramphenicol resistance) | 43 | 0.460 | 43 |
| pC221mobA1 | pC221 with 75-bp deletion between the MwoI sites | <5 | 0.038 | This study |
| pC221mobA4 | pC221 with extra 1 bp at the ScrFI site | <5 | 0 | This study |
| pC221mobAB2 | pC221 with extra 4 bp at the EcoRI site | 19 | 0 | This study |
| pC221mobC1 | pC221 with extra 2 bp at the ClaI site | <5 | 0 | This study |
| pC221cop903 | pC221cop903 high-copy-number mutant of pC221 | 75 | NT | 51 |
| pC221mobA2 | pC221cop903 with extra 5 bp at the SexAI site | <5 | NT | This study |
| pC221mobB1 | pC221cop903 with extra 4 bp at the HindIII site | 52 | NT | This study |
| pC221mobC3 | pC221cop903 with extra 4 bp at the XbaI site | 74 | NT | This study |
| pC223 | pC223 wild type (inc10, chloramphenicol resistance) | 32 | 0.150 | 41 |
| pC223mobA3 | pC223 with 461-bp deletion between the BsgI and BbvI sites | <5 | 0 | This study |
| pC223mobAB1 | pC223 with 4-bp deletion at the BanII site | 27 | 0 | This study |
| pC223mobC4 | pC223 with fortuitous 1-bp deletion at the ClaI site | <5 | 0 | This study |
| pC223mobC5 | pC223 with a BclI site engineered adjacent to the ClaI site | <5 | 0 | This study |
| pC223oriT1 | pC223 with replacement of the 374-bp BstEII-BstBI fragment from pC221 | <5 | 0 | This study |
| pC223oriT2 | pC223 with replacement of the 374-bp BstEII-BstBI fragment from pC221cop903 | -c | -c | This study |
| pC221oriT3 | pC221 with replacement of the 360 bp BstEII-BstBI fragment from pC223 | <5 | 0.023 | This study |
| pC221oriT4 | pC221cop903 with replacement of the 360-bp BstEII-BstBI fragment from pC223 | 14 | NT | This study |
| pGO1 | Self-transmissible, gentamicin resistance | 3 |
a
Relative percentage of total plasmid DNA measured in the relaxed, open circular form (OC) after agarose gel electrophoresis of whole-cell lysates (results of three to six separate determinations).
b
Ratio of chloramphenicol-resistant to gentamicin-resistant recipients after filter mating (result of at least three separate experiments; representative data are shown). NT, not tested.
c
Plasmids pC223oriT1 and pC223oriT2 are identical.