Table 1.

Strains and plasmids used

Strain or plasmidRelevant genotype or phenotypeReference or source
E. coli DH5αF′/endA1 hsdR17 supE44 thi-1 recA1 gyrA relA1 Δ(lacZYA-argF)U169 deoR [φ80dlacZΔM15 recA1] 40
P. aeruginosa
 PAO1 Wild-type, elastolytic, prototroph12
 PAO-R1ΔlasR::Tcr, nonelastolytic derivative of strain PAO18
 PR1-E4ΔlasR::Tcr, casein incubation-induced elastolytic mutant of strain PAO-R136
 PDO100ΔrhlI::Tn501-2derivative of PAO13
Plasmids
 pBluescript II SK+ General-purpose cloning vector, ori(ColE1), Apr Stratagene
 pUC18, pUC19General-purpose cloning vectors, ori(ColE1)Gibco
 pUCP18, pUCP19, pUCP24 E. coli-P. aeruginosa shuttle vectors30
 pRL1500pUCP19 containing rhlA on a 1.5-kb BglI-NcoI fragment from strain PG20118
 pPAO-2pUC19 containing a 280-bp Sau3A fragment of pilA from strain PAO129
 pJPP41pBluescript II SK+ containingrhlI on a 950-bp BglII-SphI fragment from strain PAO125
 pRB1801pUC18 containing a 1.75-kbEcoRI-SmaI fragment of lasB from strain PAO12
 GB24 P. aeruginosa gene bank: partial Sau3A digest of strain PAO1 DNA inserted into theBamHI site of pUCP24U. Ochsner
 pVD99.0pUCP24 containing a 2.5-kb Sau3A genome fragment from strain PAO1This study
 pVD99.1pUCP24 containing a 1.98-kbEcoRI fragment from pVD99.0This study
 pVD99.3pUCP24 containing dksA on a 960-bpSmaI fragment from pVD99.0This study
 pVD99.4pUCP24 containing a 523-bp EcoRI fragment from pVD99.0This study
 pVD99.5pUCP24 containing a 520-bpSalI fragment from pVD99.0This study
 pECP60pSW205 containing a rhlA′-lacZ translational fusion26
 pDECP60pECP60 containing dksA on a 960-bp SmaI fragment from pVD99.3This study
 pLPR1pLP170 containing a rhlI′-lacZtranscriptional fusion36
 pVDpLPRI containingdksA on a 960-SmaI fragment from pVD99.3This study
 pPBL25pUCP18 containing lasB′-lacZ on a 3-kbEco0109 fragment from pKDT37 (22)This study
 pPBLD26pPBL25 containing dksA on a 960-bpSmaI fragment from pVD99.3This study