TABLE 1.
Bacterial strains and plasmids used in this study
| Strain or plasmid | Descriptiona | Source or reference |
|---|---|---|
| P. aeruginosa strains | ||
| PAO1 | Prototroph | |
| OCR1 | MexA-MexB-OprM-overproducing, nalB-type multidrug-resistant derivative of PAO1 | 17 |
| KG2212 | mexR::res-Ω of PAO1 | This study |
| KG2239 | ΔmexR-mexA-mexB-oprM of PAO1 | This study |
| KG3052 | Intermediately MexC-MexD-OprJ-overproducing, type-A nfxB multidrug-resistant derivative of PAO1 (formerly COR2) | 19 |
| KG2217 | mexR::res-Ω of KG3052 | This study |
| KG2240 | ΔmexR-mexA-mexB-oprM of KG3052 | This study |
| KG3056 | Highly MexC-MexD-OprJ-overproducing, type-B nfxB multidrug-resistant derivative of PAO1 (formerly COR6) | 19 |
| KG2236 | mexR::res-Ω of KG3056 | This study |
| KG2259 | ΔmexR-mexA-mexB-oprM of KG3056 | This study |
| Plasmids | ||
| pMT5059 | pBend2 derivative carrying the multiple-cloning site and NotI site; Apr | 33 |
| pKMM089 | pMT5059 derivative carrying a 2.6-kb XhoI-HindIII fragment from pPV20; Apr | This study |
| pKMM091 | pKMM089 derivative carrying NotI-flanked res-tnpR block from pMT5085; Apr Tcr | This study |
| pKMM102 | pMT5059 derivative carrying mexR, mexA, mexB, and a part of oprM on a 24-kb PvuII-XhoI fragment; Apr | This study |
| pKMM127 | pKMM102 derivative carrying SacI-flanked res-Ω cassette from pMT5096 and NotI-flanked Mob cassette from pMT5071; Apr Cmr | This study |
| pKMM151 | pMT5059 ori-carrying plasmid rescued from KG2213 chromosome; Apr | This study |
| pKMM157 | pKMM089 derivative carrying SacI-flanked res-Ω cassette from pMT5095 and NotI-flanked res-tnpR block from pMT5085; Apr Smr Tcr | This study |
| pMP190 | Broad-host-range, low-copy-number lacZ fusion vector; Cmr Smr | 31 |
| pKMM301 | pMP190 derivative carrying the mexR-mexA intergenic region on a 276-bp PCR product amplified with mexR7-mexA3, with the mexA promoter oriented towards the promoterless lacZ gene; Cmr Smr | This study |
a
Abbreviations: Apr, ampicillin resistant; Cbr, carbenicillin resistant; Cmr, chloramphenicol resistant; Kmr, kanamycin resistant; Smr, streptomycin resistant; and Tcr, tetracycline resistant.