Table 2.

Production of virulence factors by PAO1 and ΔpppA-ppkA and MIC profiles

	Strain
	PAO1			ΔpppA-ppkA
Virulence factor	24 h	48 h	72 h	24 h	48 h	72 h
elastases - elastine degradation	+	+	+	+	+	+
elastases - casein degradation			+			+
pyocyanin	+	+	+	+	+	+
pyoverdine (OD405/OD600)a	0.68 (± 0.032)			0.39 (± 0.054)
phospholipase C	+			+
swarming motility	+			+
swimming motility	+			+
twitching motility			+			+
alginate		+			+
MIC (μg•ml-1)b	PAO1			ΔpppA-ppkA
chloramphenicol	25			55
carbenicillin	35			75

+ sign indicates positive reaction or manifestation

^a The pyoverdine values are expressed as OD₄₀₅ values of culture supernatants normalized to cell density at OD₆₀₀. Averages based on three independent assays are presented. The numbers in the parentheses represents standard errors of the means. The differences between the mutant and wild-type strain are statistically significant (P < 0.05).

^b The data are representative of four replicates.