TABLE 2.

Susceptibility and mRNA expression among control strains and clinical isolates of P. aeruginosa

IsolateMIC (μg/ml)aRelative gene expressionb
IPMMEMPTZCAZCTXATMCIPCARGENTOBAMKoprD*ampCmexAmexCmexEmexX
Controls
    M125148324128320.55120.50.251 0.29 1.78 7.28 1.24 2.50 2.70
    R7016>32328256640.5>51210.51 0.05 5.72 5.94 1.721.32 7.94
    R2020.58144≤0.1264≤0.250.5≤0.5 3.27 0.730.750.77 0.30 1.79
    AHP0.120.2540.540.5≤0.1232≤0.12≤0.12≤0.51.23 0.004 0.12 0.02 0.01 0.02
    Z799/610.5≤0.06≤1≤0.120.5≤0.12≤0.12≤16≤0.120.251 0.15 0.12 0.12 0.24 0.01 0.08
    2779-con21>6432>25632≤0.121280.511 5.34 313 1.560.99 4.90 3.71
    1405-con D2168>6464>256640.25512224 0.35 599 6.92 2.62 2.26 1.22
Clinical isolates
    1530c80.5≤1432286432432 0.06 1.130.650.691.23 11.6
    1693c82≤18128111281621 0.08 0.42 2.60 0.38 0.24 0.29
    17145c3242641280.54≤16321664 0.0004 8.40 0.39 0.11 0.33 2.55
    1529c16424320.588>321664 0.12 3.29 0.56 0.18 1.18 12.4
    14169c1648812864151232432 0.07 35.9 2.52 1.05 0.42 4.39
    1247c1644812844128>328>64 0.018 36.4 1.810.75 0.44 2.96
    1681c328>64256>256322512321664 0.006 11.5 4.90 0.31 0.34 5.85
    1352c>32166464>256322512>3216>64 0.004 10.8 1.82 0.49 0.89 6.41
    1333c3216>64128>256>642>512>32864 0.0007 368 2.66 1.77 9.01 33.9
    1248c161632256>256>644>512>3232>64 0.012 5.89 4.11 0.701.31 11.7
    15110c>3216>64256>256>642>512>32>32>64 0.05 474 5.61 1.000.7 2.37
    12142c3232>64256>256>644>512>32>32>64 0.0004 262 15.9 3.1 3.7 6.52
    1712c3232>64>256>256>644>512>3216>64 0.015 160 1.831.2 2.98 18.9
    1495c>32>32>64>256>256>644>512>648>64 0.06 284 3.49 2.92 6.91 78.3
    172640.12≤12160.52≤1620.52 0.25 1.501.08 0.21 0.10 1.80
    151078232825620.25128>322>64 0.03 1.361.871.06 0.26 10.5
    16008644≤11640.54≤1616432 0.003 0.09 0.56 0.09 0.03 27.1
    1316744464>256168>512324641.53 7.22 3.51 0.76 0.4 1.17
    124016882562564212820.54 0.08 110 1.3011.82 2.10
    31493281686464>8>512>32>32>64 0.007 10.5 4.87 1.35 0.37 0.3
    12102321616464162256414 0.0006 0.79 2.46 1.511.02 11.8
    1253>323264812816225616432 0.008 4.17 1.96 5.2 7.8 13.3
    131201632164128160.52560.50.2510.9 2.04 2.30 0.87 0.4 15.0
    166564>32>64256>256>644>5121632>64 0.0001 150 5.89 1.651.140.51
    17112128>326464>256>64251210.51 0.03 44.1 3.12 0.17 0.08 0.11
  • a IPM, imipenem; MEM, meropenem; PTZ, piperacillin-tazobactam; CAZ, ceftazidime; CTX, cefotaxime; ATM, aztreonam; CIP, ciprofloxacin; CAR, carbenicillin; GEN, gentamicin; TOB, tobramycin; AMK, amikacin.

  • b Increased or decreased gene expression relative to P. aeruginosa PAO1 (which was assigned a value of 1.0) was defined by expression values of ≥2 and ≤0.5, respectively, and is indicated in bold.

  • c Isolate belonging to the Liverpool epidemic strain.