Table I. Stability of miniP1 plasmids with mutant ParA proteins.
| Plasmid providing Par proteins (ParA allele) | Percentage retention of miniP1 (pBEF250) after overnight growth |
|---|---|
| pEF5.1 (wild-type) | 85 ± 4 |
| pEF5.2 (D251N) | 14 ± 2 |
| pEF5.3 (D251H) | 12 ± 2 |
| pEF5.4 (D152H) | nda |
| pEF5.5 (D152N) | 34 ± 2 |
| pEF5.6 (K122Q) | 15 ± 5 |
| pEF5.7 (K122E) | 22 ± 3 |
| pEF5.8 (K122R) | nda |
| pBEF251 (ΔparA) | 10 ± 5 |
| pBR322 (no parA or parB) | 28 ± 5 |
‘Retention’ represents the ratio of the frequency of cells with pBEF250 after overnight growth divided by the frequency of cells with pBEF250 at the start, expressed as a percentage. The data represent the average of 3–5 independent experiments, depending on the pEF5 derivative.
and, not determined by this assay. Colonies containing pBEF250 with these plasmids grew extremely slowly in the presence of ampicillin and choramphenicol (see Results).