TABLE 3.
Complementation analysis of the ΔmbeC plasmid pUIV248a
| Complementing plasmid | Mobilization frequency (SD) |
|---|---|
| pET29c (negative control) | <10−7 |
| pUIV248 (ΔmbeC, negative control) | <10−7 |
| pUIV239 (pET29c::mbeC cloned from the first ATG) | 3 × 10−2 (1 × 10−2) |
| pUIV236 (pET29c::mbeC cloned from the second ATG) | 3 × 10−6 (1 × 10−6) |
| pUS4601 (ColE1::Km, positive control) | 4 × 10−2 (2 × 10−2) |
| pUIV262 (R13A mutant) | 1 × 10−5 (0.5 × 10−5) |
a
Derivatives of E. coli strain BL21(DE3) carrying pUIV248 and each of the plasmids shown in the first column were separately used as donors in triparental matings using DH5α/R64drd-11 as the helper and HMS174 as the final recipient. After filter mating, bacteria were plated on selective media containing Rif to counterselect donors and Cm to select for pUIV248 mobilization. Transfer frequencies are expressed as the number of transconjugants per recipient cell and are the average of at least three separate experiments.