Table 2.

Restoration of rhlA and lasBexpression by exogenous C4-HSLa

Fusion Enzyme activity (Miller units)
PAO1PR1-E4
dksA+dksA+dksA + 10 μM C4-HSL dksA+dksA+dksA + 10 μM C4-HSL
rhlA′-lacZ 6,830 ± 6254,200 ± 600 7,350 ± 650 390 ± 45 54 ± 8372 ± 32
lasB′-lacZ NDNDND 379 ± 40110 ± 10594 ± 42
  • a Cultures of PAO1 and mutant PR1-E4 carrying the indicated reporter fusions were grown for 8 h (OD660 = 1.8 ± 0.1), and β-Gal activity was assayed. Data are the mean ± 1 standard deviation of at least two separate experiments performed in triplicate. −dksA, pECP60 (rhlA′-lacZ) or pPBL25 (lasB′-lacZ); +dksA, pDECP60 (rhlA′-lacZ dksA) or pPBLD26 (lasB′-lacZ dksA). ND, not determined.