Table 1. Induction of BlaPβ-lactamase of the BlaR1 L3 loop mutants.
Mutation | Plasmids | Induction factor* (3h) | |
Wild type | pDML995 | 37.8±1.5 | |
Mutants in H212EXXH motif | H212A/E213A/H216A | pDML1268 | 1.6±0.1 |
E213A | pDML1269 | 1.2±0.1 | |
H212A/H216A | pDML1270 | 1.2±0.1 | |
H216A | pDML1271 | 1.27±0.01 | |
E213D | pDML1279 | 1.07±0.02 | |
E213Q | pDML1280 | 1.6±0.2 | |
Mutants in putative Zn++ ligands | D221A | pDML1277 | 1.2±0.1 |
E253A | pDML1273 | 1.2±0.3 | |
D257A | pDML1274 | 1.9±0.1 | |
E274A | pDML1275 | 33.9±0.9 | |
Mutants in putative general base | Y 272A | pDML1278 | 1.1±0.1 |
Mutants in R304R cleavage site | R304A/R305A | pDML3045 | 7.6±1.7 |
The induction factor corresponds to the ratio between the β-lactamase quantity/A600 for induced culture and the β-lactamase quantity/A600 for uninduced culture.