Table 1.
Susceptibility and resistance mechanisms of PAO1 and PAOMS biofilm CIP-resistant mutants
| Origin of mutants (n)a | No. of mutants with a defined phenotype | CIP MIC range (μg/ml) | Resistance mechanism(s)b |
|---|---|---|---|
| PAO1 | 0.125 | None | |
| PAOMS | 0.125 | None | |
| PAO1 CIP 0.5 (12) | 12 | 0.75–2 | mexF overexpression |
| PAOMS CIP 0.5 (12) | 7 | 0.75–2 | mexD overexpression |
| 5 | 1–2 | mexF overexpression | |
| PAOMS CIP 2 (12) | 5 | 8–24 | mexD overexpression + GyrA Thr-83-Ala |
| 1 | 4 | mexF overexpression + GyrA Thr-83-Ala | |
| 2 | >32 | mexF overexpression + GyrA Thr-83-Ile | |
| 1 | >32 | mexD overexpression + GyrB Ser-466-Phe | |
| 1 | >32 | mexF overexpression + GyrB Ser-466-Phe | |
| 1 | 6 | mexD overexpression + GyrB Ile-480-Thr | |
| 1 | 4 | mexF overexpression + ? |
a
Collected at t4 (i.e., 4 days of CIP treatment).
b
That is, mutations in topoisomerases (the numbering corresponds to the published PAO1 sequence).