Table 2 Influence of porins on antibiotic activity in E. coli transformants expressing oprD/Occd1, opdK/occK1, or opdF/occK2.

From: Mechanisms of intrinsic resistance and acquired susceptibility of Pseudomonas aeruginosa isolated from cystic fibrosis patients to temocillin, a revived antibiotic

Strains

Antibiotic MIC (mg/L) a

TMO

FOX

IPM

MEM

control

+PAβN b

control

+PAβN b

W3110 ΔompF/C + pBAD-Empty

40

18

80

20

1

1.5

W3110 ΔompF/C + pBAD-oprD

40

18

80

20

0.225

0.225

W3110 ΔompF/C + pG-Empty

40

18

80

20

1

1.5

W3110 ΔompF/C + pG-opdK clone 1c

20

9

56

16

1

1.5

W3110 ΔompF/C + pG-opdK clone 2c

20

9

56

16

1

1.5

W3110 ΔompF/C + pG-opdF clone 1c

22

14

60

18

1

1.5

W3110 ΔompF/C + pG-opdF clone 2c

22

14

60

18

1

1.5

  1. aMICs (mg/L) of temocillin (TMO), cefoxitin (FOX), imipenem (IPM), and meropenem (MEM) were determined in the presence of Isopropyl β-D-1-thiogalactopyranoside (IPTG) 0.5 mM or arabinose 0.5% as gene inducers. Values in bold highlight increased activity vs. the corresponding control (no porin expressed).
  2. b20 mg/L PAβN added as an inhibitor of E.coli AcrAB-TolC efflux pump.
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