Table 2.
Strain | PAEa(h) | PAEPb (h) | Antibiotic (MIC)c | Final concentration in μg/mL (times x MIC) | S-PAEPd (h) | ||
---|---|---|---|---|---|---|---|
0 | 1 | 2 | |||||
Ps4 | 1.45 + 0.02 | 2–3 | NOV (512) | 64 (1/8) | 4.8 + 0.1 | 2.7 + 0.05 | 0.45 + 0.01 |
2–3 | FOS (512) | 64 (1/8) | 2.27 + 0.05 | 2.12 + 0.04 | 1.60 + 0.03 | ||
2–3 | RIF (16) | 2 (1/8) | 0.6 + 0.01 | 0.6 + 0.01 | 0.25 + 0.01 | ||
2–3 | ERY (128) | 16 (1/8) | 1.04 + 0.02 | 0.82 + 0.02 | 0.78 + 0.02 | ||
2–3 | CAZ (64) | 16 (1/4) | 14.24 + 0.3 | 14.24 + 0.3 | 1.56 + 0.03 | ||
2–3 | CAZ (64) | 4 (1/16) | 2.0 + 0.04 | 1.25 + 0.03 | 0.1 + 0.01 | ||
2–3 | CEF (1024) | 512 (1/2) | 0.8 + 0.02 | 0.7 + 0.01 | 0.7 + 0.01 | ||
n.fe | CIP (2) | 0.25 (1/8) | 0.7 + 0.01 | < 0.25 | < 0.25 | ||
PAO1 | 1.9 + 0.03 | 2–3 | NOV (1024) | 64 (1/16) | 7.81 + 0.16 | 2.58 + 0.05 | 0.87 + 0.02 |
LC1–6 | 0.75 + 0.04 | 2–3 | NOV (8192) | 512 (1/16) | 7.62 + 0.15 | 4.29 + 0.1 | 0.87 + 0.02 |
PAΔADD | 1.2 + 0.026 | 2–3 | CAZ (64) | 16 (1/4) | 4.27 + 0.1 | 3.42 + 0.07 | 3.32 + 0.07 |
h2Dh3 |
a Post-antibiotic effect assessed by turdidimetry (Bioscreen). PAEs y S-PAEPs values are the average of three and two independent experiments, respectively, each of them performed in triplicate. Differences were analyzed by Kruskal–Wallis test followed by Mann–Whitney’s U test
b Duration of Post-Antibiotic Effect-associated Permeabilization
c NOV, novobiocin; FOS, fosfomycin; RIF, rifampin; ERY, erythromycin; CAZ, ceftazidime; CEF, cephalothin; CIP, ciprofloxacin. MICs (μg/mL) are in parenthesis
d Score of Post-Antibiotic Effect-associated Permeabilization. Delay in h caused by exposure to a sub-MIC concentration of an antibiotic added at the indicated time (0 h, 1 h, 2 h) after the beginning of growth in peptide-free medium. S-PAEP was assessed by turdidimetry (Bioscreen)
e Determination was not feasible due to resistance to antibiotic