Table 3.
MIC50 values for penicillin G garvicin KS and micrococcin P1 determined in liquid culture for the indicated strains.
| Antimicrobial (mg/ml) | Strain | |||||
|---|---|---|---|---|---|---|
| ATCC 10832 | Newman | USA 300 | ATCC 29213 | ATCC 33591 | S.a. 3255 | |
| Individual components | ||||||
| Penicillin G | <7.8 × 10−3 | <7.8 × 10−3 | >1 | 1.3 × 10−1 | >1 | <7.8 × 10−3 |
| Combination | ||||||
| Garvicin KS | <7.8 × 10−4 | <7.8 × 10−4 | 2.5 × 10−2 | 1.3 × 10−2 | 5 × 10−2 | <7.8 × 10−4 |
| Penicillin G | <7.8 × 10−3 | <7.8 × 10−3 | 2.5 × 10−1 | 1.3 × 10−1 | 5 × 10−1 | <7.8 × 10−3 |
| FICa | ND3 | ND3 | 1.25 | 1.52 | 1.5 | ND3 |
| Combination | ||||||
| Garvicin KS | <7.8 × 10−4 | <7.8 × 10−4 | 6.3 × 10−3 | 3.1 × 10−3 | 1.3 × 10−2 | <7.8 × 10−4 |
| Micrococcin P1 | <7.8 × 10−5 | <7.8 × 10−5 | 6.3 × 10−4 | 3.1 × 10−4 | 1.3 × 10−3 | <7.8 × 10−5 |
| Penicillin G | <7.8 × 10−3 | <7.8 × 10−3 | 6.3 × 10−2 | 3.1 × 10−2 | 1.3 × 10−1 | <7.8 × 10−3 |
| FICb | ND3 | ND3 | 1.32 | 0.49 | 0.52 | NDc |
aSynergy achieved with fractional inhibition concentration (FIC) ≤ 0.5, for two components.
bSynergy achieved with fractional inhibition concentration (FIC) ≤ 0.75, for three components.
cNot determined. The MIC values exceeded the minimum concentration tested: penicillin G, 7.8 × 10−3 mg/ml; micrococcin P1, 7.8 × 10−5 mg/ml; garvicin KS 7.8 × 10−4 mg/ml.