Table 1. Strains used in this study.
| Strain or plasmid | Description | Source or reference |
| P. aeruginosa strains | ||
| PAO1 | Wild type | [36] |
| ΔpstS | PAO1 with an unmarked deletion of pstS | This study |
| ΔphoB | PAO1 with an unmarked deletion of phoB | This study |
| ΔpstSΔphoB | PAO1 with an unmarked deletion of pstS and phoB | This study |
| ΔrhlA | PAO1 with an unmarked deletion of rhlA | This study |
| ΔrhlR | PAO1 with an unmarked deletion of rhlR | This study |
| ΔpstSΔrhlA | PAO1 with an unmarked deletion of pstS and rhlA | This study |
| ΔpstSΔrhlR | PAO1 with an unmarked deletion of pstS and rhlR | This study |
| E. coli strains | ||
| DH5α | F′/endA1 hsdR17 supE44 thi-1 recA1 gyrA relA1 Δ(lacZYA-argF) U169deoR (Φ80 dlacZ-M15 recA1) | [37] |
| S17.1 (λpir) | recA derivative of E. coli 294 (F- thi pro hsdR) carrying a modifiedderivative of IncPα plasmid pRP4 (Aps Tcs Kms) integrated in thechromosome, Tpr; lysogenized with bacteriophage λpir | Y. Irie and M. R. Parsek |
| Plasmids | ||
| pUCP18Ap | A broad-host range cloning vector. CbR/AmpR | [38] |
| DB3.1 pEX18GmGW | pEX18Gm containing the Gateway (GW) destination cloning site. GmR | Nan Fulcher and Matthew Wolfgang |
| pphoB | pUCP18Ap containing the phoB gene for complementation | This study |
| ppstS | pUCP18Ap containing the pstS gene for complementation | This study |
| prhlA | pUCP18Ap containing the rhlA gene for complementation | This study |
| prhlR | pUCP18Ap containing the rhlR gene for complementation | This study |
| pECP61.5 | Contains a rhlA-lacZ fusion, used for C4-HSL detection | [11] |
AmpR -Ampicilin resistance for E. coli CbR – Carbenicillin resistance for P. aeruginosa. GmR – Gentamicin resistance.