Table 3.
MIC (µg/ml) of ampicillin-tetramic acid hybrids against gram-negative bacteria in presence of clavulanic acid.
| Compounds clavulanic acid (6µg/ml) |
EC | KP | ECΔampC | PA | ||||
|---|---|---|---|---|---|---|---|---|
| + | − | + | − | + | − | + | − | |
| ampicillin | 1.56 | 3.13 | 25 | 100 | 1.56 | 3.13 | 100 | >200 |
| piperacillin | 3.13 | 6.25 | 6.25 | 6.25 | 1.56 | 1.56 | 3.13 | 6.25 |
| 1903 | 12.5 | 50 | 25 | 200 | 1.56 | 6.25 | 6.25 | 12.5 |
| 1905 | 12.5 | 25 | 100 | 200 | 12.5 | 25 | 12.5 | 25 |
| 1940 | 12.5 | 50 | 25 | >200 | 6.25 | 12.5 | 12.5 | 25 |
| 2742 | 25 | 100 | 100 | >200 | 12.5 | 25 | 12.5 | 25 |
| 2743 | 12.5 | 200 | 25 | >200 | 6.25 | 12.5 | 12.5 | 25 |
| 2744 | 25 | 100 | 25 | >200 | 12.5 | 25 | 25 | 25 |
| 2745 | 12.5 | 100 | 25 | >200 | 6.25 | 6.25 | 25 | 25 |
| 2746 | 50 | 200 | >200 | >200 | 25 | 50 | 25 | 50 |
| 2780 | 50 | 200 | 25 | >200 | 3.13 | 12.5 | 12.5 | 25 |
| 2781 | 6.25 | 100 | 50 | >200 | 3.13 | 6.25 | 3.13 | 12.5 |
| 2782 | 3.13 | 25 | 50 | >200 | 3.13 | 6.25 | 12.5 | 25 |
| 2833 | 12.5 | 100 | 100 | 200 | 6.25 | 12.5 | 6.25 | 25 |
| 2835 | 6.25 | 100 | 100 | 200 | 12.5 | 50 | 6.25 | 25 |
| 2916 | 12.5 | 50 | 100 | >200 | 3.13 | 6.25 | 6.25 | 25 |
| 2917 | 12.5 | 12.5 | 50 | >200 | 12.5 | 25 | 6.25 | 25 |
| 2918 | 12.5 | 6.25 | 50 | >200 | 6.25 | 25 | 6.25 | 50 |
| 2919 | 50 | 12.5 | 100 | 200 | 6.25 | 12.5 | 12.5 | 50 |
| 3002 | 6.25 | 6.25 | 25 | 200 | 6.25 | 6.25 | 3.13 | 12.5 |
Key: EC= E. coli BW25113; KP= K. pneumoniae ATCC 13883; PA= P. aeruginosa PA01; ECΔampC – E. coli BW25113 ΔampC derivative JW4111-2. Clavulanic acid MICs were 100 µg/ml against EC and KP; 200 µg/ml against PA; and 25 µg/ml against ECΔampC.