Table 2.

Effect of smeE and smeF deletions on antimicrobial susceptibility of S. maltophilia

Antimicrobial agentMIC (μg/ml) fora
ULA-511 (wild type) K1765 (ULA-511 ΔsmeE) K1793 (ULA-511 ΔsmeF) K1449 (ULA-511 ΔL1/ΔL2)K1766 (K1449 ΔsmeE) K1795 (K1449 ΔsmeF) K1385 (ULA-511 MDR) K1767 (K1385 ΔsmeE) K1794 (K1385 ΔsmeF) K1439 (ULA-511 MDR) K1768 (K1439 ΔsmeE) K1796 (K1439 ΔsmeF)
Quinolones
 Nalidixic acid16 4 4 8 4 4 64 64 464 64 64
 Norfloxacin 16 4 8 16 44 128 128 16 128 32 64
 Ciprofloxacin8 2 2 4 1 1 32 32 4 64 3232
 BAYy3118 0.06 0.015 0.015 0.06 0.0150.015 1 0.5 0.06 1 1 1
 Clinafloxacin0.125 0.032 0.064 0.125 0.032 0.032 10.5 0.125 2 2 2
 Gemifloxacin 1 0.250.5 1 0.25 0.25 8 4 1 8 8 8
 Moxifloxacin 0.5 0.125 0.25 0.5 0.060.125 4 2 1 8 8 8
 Trovafloxacin0.25 0.125 0.25 0.25 0.125 0.125 8 80.5 8 8 8
Tetracyclines
 Tetracycline8 2 4 8 2 2 16 16 4 8 44
 Doxycycline 0.5 0.125 0.25 0.5 0.250.25 4 4 0.5 2 2 2
 Minocycline0.125 0.06 0.06 0.125 0.06 0.06 1 10.25 0.25 0.25 0.125
 Tigilcycline 0.50.125 0.25 0.5 0.125 0.25 2 2 0.250.5 0.25 0.125
Macrolides
 Erythromycin512 128 256 512 128 128 1,024 1,024512 512 128 128
 Azithromycin 256 128128 128 128 128 512 512 256 128 6464
β-Lactams
 Penicillin GNDb ND ND 1 1 0.5ND ND ND ND ND ND
 Ampicillin ND ND ND 2 2 0.5 ND NDND ND ND ND
 Carbenicillin ND ND ND1 0.5 0.5 ND ND ND ND ND ND
 Piperacillin ND ND ND 2 1 1 ND NDND ND ND ND
 Cefuslodin ND ND ND 22 1 ND ND ND ND ND ND
 CefotaximeND ND ND 1 1 0.5 ND ND ND NDND ND
 Cefoperazone ND ND ND 2 1 1ND ND ND ND ND ND
 Cefepime ND NDND 0.5 0.25 0.25 ND ND ND ND NDND
 Cefpirome ND ND ND 0.5 0.25 0.25ND ND ND ND ND ND
 Imipenem ND NDND 0.25 0.25 0.25 ND ND ND ND NDND
 Meropenem ND ND ND 0.125 0.06 0.06ND ND ND ND ND ND
 Pirazmonam NDND ND 0.5 0.5 0.5 ND ND ND NDND ND
Other antibiotics
 Chloramphenicol8 4 4 8 4 4 64 64 1664 64 64
 Kanamycin 1,024 1,024 1,0241,024 1,024 512 256 256 128 1,024 1,0241,024
 Novobiocin 2,560 1,280 1,280 2,5601,280 1,280 5,120 5,120 2,560 5,120 5,1202,560
 Rifampin 8 8 8 8 8 8 1616 8 16 16 16
D-Cycloserine512 512 512 512 512 256 512 512 2561,024 1,024 512
 Trimethoprim 16 16 816 16 8 128 128 64 128 128 128
Toxicants
 SDS 3,200200 400 3,200 200 400 3,200 3,200 4003,200 1,600 800
 Crystal violet 16 8 816 4 4 32 32 16 32 32 16
 Acriflavine 256 64 128 256 32 32>256 >256 256 256 128 256
 Proflavine>256 64 128 >256 64 128 >256 >256256 >256 256 >256
 Ethidium bromide 51264 128 512 64 64 1,024 512 2561,024 512 512
  • a MICs for isogenic pairs of SmeE+ and SmeE strains are shown. Relevant phenotypes are highlighted below strains.

  • b ND, not determined due to the production of L1 and L2 β-lactamases in these strains.