TABLE 2.

Synergistic activities of tested antibiotic combinations

Peptide antibioticNonpeptide antibioticMIC, μg/ml (concn, μM)FIC index
Peptide antibioticNonpeptide antibiotic
NonsynergySynergyNonsynergySynergy
ΔFmRifampin135.8 (100)8.4 (6.2)3.6 (4.4)0.9 (1.1)0.3
Kanamycin135.8 (100)33.9 (25)2.1 (3.6)0.5 (0.9)0.5
ΔFmscrRifampin67.9 (50)2 (1.5)3.6 (4.4)0.4 (0.5)0.14
Kanamycin67.9 (50)16.9 (12.5)2.1 (3.6)0.5 (0.9)0.5
UdRifampin73.9 (30)4.4 (1.8)3.6 (4.4)0.4 (0.5)0.17
ΔFqKanamycin21.3 (3.7)5.1 (0.9)2.1 (3.6)0.5 (0.9)0.5