TABLE 2.

β-Galactosidase activities of two transcriptional hcnA-lacZ fusions constructed at T1 and T2 in P. aeruginosa wild type and regulatory mutants^a

Strain (genotype)	β-Galactosidase activity (Miller units)
	pME3850.1 (P1)	pME3850.2 (P1+P2)
PAO1 (wild type)	2,299 ± 259	3,971 ± 183
PAO6261 (anr)	1,887 ± 80	2,721 ± 111
PDO111 (rhlR)	186 ± 32	281 ± 4
PAO6330 (lasRI)	99 ± 1	98 ± 1

^aStrains were grown in 40 ml of MMC in 100-ml Erlenmeyer flasks at 37°C with shaking to an OD₆₀₀ of 1.0 and 1.2. β-Galactosidase activities were determined in triplicate; means ± standard deviations of three independent experiments are given. The hcnA-lacZ transcriptional fusion constructs are shown in Fig. 2D.