TABLE 2.
Relative protein expression levels and transport activities of representative TetA(K) motif C mutants
| Mutation | TetA(K) protein expression (%)a | Relative tetracycline transport activity (%)b |
|---|---|---|
| G151 mutations | ||
| G151V | 92.0 | 28.0 |
| G151L | 117.4 | 4.3 |
| G151A | 110.1 | 88.3 |
| G151S | 80.6 | 103.3 |
| G155 mutations | ||
| G155A | 141.4 | 30.0 |
| G155P | 82.8 | 6.3 |
| G155S | 143.4 | 22.2 |
| G155T | 112.1 | 13.1 |
| P155S-P156S | 134.6 | 31.6 |
| P156 mutations | ||
| P156A | 91.1 | 16.1 |
| P156V | 104.0 | 13.8 |
| P156G | 82.7 | 27.2 |
| P156S | 93.0 | 12.5 |
| G159 mutations | ||
| G159A | 101.1 | 14.4 |
| G159P | 24.7 | 24.3 |
| G159S | 87.7 | 20.1 |
| G159V | 64.9 | 15.9 |
| G160 mutations | ||
| G160V | 142.4 | 19.5 |
| G160L | 110.7 | 5.0 |
| G160A | 103.6 | 42.9 |
| G160S | 120.1 | 31.1 |
a
TetA(K) expression levels were normalized using a host-encoded protein (see Materials and Methods for details) and are expressed as a percentage of the level detected with the wild-type TetA(K) encoded by pSK4646 (Table 1).
b
Tetracycline transport activity, corrected for the TetA(K) protein expression levels shown, is represented as a percentage of wild-type TetA(K) transport activity.