TABLE 1.
E. coli strain | β-Lactamase activity (U/mg of bacterial protein) | MIC (μg/ml)a
|
|||||
---|---|---|---|---|---|---|---|
AMP | CET | CXM | CFX | ATM | IMP | ||
AS226-51 (host cell) | <10−5 | 0.8 | 0.8 | 1.6 | 1.6 | <0.2 | <0.2 |
AS226-51/RDK4 | 0.098 | 25 | 100 | 100 | 200 | <0.2 | 1.6 |
AS226-51/RDK4-1 | 0.14 | 100 | 400 | 400 | 800 | <0.2 | 3.1 |
AS226-51/RDK4-2 | 0.62 | 200 | 400 | 800 | 800 | <0.2 | 6.3 |
AS226-51/RDK4-3 | 0.67 | 200 | 400 | 800 | 1,600 | <0.2 | 12.5 |
AS226-51/RDK4-4 | 0.90 | 200 | 400 | 800 | 1,600 | <0.2 | 12.5 |
AS226-51/RDK4-5 | 1.30 | 200 | 400 | 800 | 1,600 | <0.2 | 12.5 |
The following β-lactams were used: ampicillin (AMP), cephalothin (CET), cefuroxime (CXM), cefoxitin (CFX), aztreonam (ATM), and imipenen (IMP).