TABLE 2.
Influence of MexA mutations on MexA-MexA interactiona
| Plasmid | MexA mutation | β-Galactosidase activityb (Miller units) |
|---|---|---|
| pMS604 | 386 ± 9 | |
| pDN14 | Wild type | 56 ± 4 |
| pDN15 | P68S | 21 ± 3 |
| pDN16 | G72S | 247 ± 8 |
| pDN17 | A108T | 64 ± 6 |
| pDN18 | V129M | 919 ± 40 |
| pDN19 | T256I | 253 ± 20 |
| pDN20 | V264E | 6 ± 1 |
| pDN21 | N270S | 8 ± 1 |
| pDN22 | H279Y | 64 ± 27 |
| pDN23 | V286A | 7 ± 6 |
| pDN24 | G297D | 206 ± 23 |
a
E. coli SU101 carrying the indicated pMS604 plasmid derivatives expressing LexA fusions to wild-type or mutant MexA was grown to late log phase and assayed for β-galactosidase activity as described in Materials and Methods. Boldface indicates that MexA-MexA interaction is compromised.
b
Results are the means ± standard deviations from two or three independent experiments carried out in triplicate.