TABLE 1.
P. aeruginosa zones of inhibition following exposure to 8 antimicrobials
| Antimicrobial | GSH | Zone of inhibition (mm)a
|
P valueb | |
|---|---|---|---|---|
| WT | ΔgshA | |||
| Hydrogen peroxide | − | 38.0 ± 0.9 | 49.6 ± 1.9 | <0.0001 |
| + | 38.3 ± 1.1 | 39.3 ± 1.2 | >0.9999 | |
| Bleach | − | 37.0 ± 2.1 | 47.4 ± 1.3 | 0.0002 |
| + | 21.3 ± 1.8 | 22.3 ± 2.2 | >0.9999 | |
| Polymyxin B | − | 13.8 ± 0.2 | 16.0 ± 0.4 | >0.9999 |
| + | 13.8 ± 0.4 | 15.2 ± 0.6 | >0.9999 | |
| Colistin | − | 15.0 ± 0.3 | 18.1 ± 0.6 | 0.4750 |
| + | 14.9 ± 0.3 | 16.0 ± 0.6 | >0.9999 | |
| Ciprofloxacin | − | 28.4 ± 0.9 | 35.8 ± 1.6 | <0.0001 |
| + | 27.9 ± 0.8 | 36.6 ± 1.6 | <0.0001 | |
| Carbenicillin | − | 19.9 ± 1.5 | 14.3 ± 0.6 | 0.0789 |
| + | 17.6 ± 1.1 | 14.4 ± 1.3 | >0.9999 | |
| Tetracycline | − | 10.9 ± 0.8 | 8.8 ± 2.7 | >0.9999 |
| + | 10.6 ± 0.7 | 12.3 ± 0.7 | >0.9999 | |
| Chloramphenicol | − | 14.3 ± 1.6 | 14.3 ± 1.2 | >0.9999 |
| + | 13.3 ± 1.0 | 13.1 ± 0.8 | >0.9999 | |
a
Values are average zone of inhibition ± standard error of the mean for P. aeruginosa WT and the ΔgshA mutant with (+) or without (–) 1 mM glutathione (GSH) added to the medium. n = 3 to 8 for each condition.
b
P values of <0.05, determined using two-way ANOVA followed by Bonferroni’s multiple-comparison test with 95% confidence interval, are in bold.