Table 3.

Pyocyanin, LasA and P_lasA-lacZ activities

Inducer*	Pyocyanin [μg (μg total protein)−1]†		LasA [ΔOD600 h−1 (μg protein)−1]‡		PlasA-lacZ (Miller units)§
	−	+	−	+	−
Alg− PAO1||	0.285±0.219	2.293±0.216¶	0.310±0.065	0.317±0.059	790.0±128.9
Alg− PAOampR||	2.934±0.761#	3.317±0.638	1.109±0.099#	0.951±0.045#	1970.5±312.6#
Alg+ PDO300	0.102±0.017**	0.324±0.051	0.135±0.011	0.147±0.024	246.5±26.5
Alg+ PDOampR	0.538±0.026††	2.518±0.640††	0.268±0.017	0.143±0.025	536.0±19.0

*Induction was carried out using 500 μg benzylpenicillin ml⁻¹ for P. aeruginosa.

†Pyocyanin concentrations were expressed as μg pyocyanin produced (μg total protein)⁻¹.

‡LasA activities were determined as the reduction of OD₆₀₀ over a period of 1 h (μg total protein)⁻¹.

§β-Galactosidase assays were performed in a high-throughput 96-well array and the results expressed in Miller units.

||These data are presented in a previous paper (Kong et al., 2005b); they are included here for comparison.

¶P<0.05 between non-induced and induced in the same strain.

#P<0.05 between Alg⁻ PAO1 and Alg⁻ PAOampR under the same conditions.

**P<0.05 between Alg⁻ PAO1 and Alg⁺ PDO300 under the same conditions.

††P<0.05 between Alg⁺ PDO300 and Alg⁺ PDOampR under the same conditions.