TABLE 3.

Expression of ackA, pta, and ldhA in wild-type P. aeruginosa and various mutants depending on oxygen tension^a

Strain	Analyzed parameter and condition
	ldhA mRNA		ackA mRNA		pta mRNA		ackA-lacZ (Miller units)		Pta activity (U/mg)d
	Aerobic	Anaerobice	Aerobic	Anaerobic	Aerobic	Anaerobic	Aerobic	Anaerobic	Aerobic	Anaerobic
Wild type	3.6 ± 0.14b	2.8 ± 1.3b	25.6 ± 1.2b	142.8 ± 32b	13.4 ± 3.0b	90.8 ± 33b	95 ± 7	355 ± 38	4.2 ± 0.5	24 ± 1.3
Δanr	NDc	2.9 ± 1.5b	ND	50.3 ± 4.1b	ND	25.1 ± 6.1b	90 ± 5	110 ± 13
dnr::tet	ND	3.3 ± 1.5b	ND	152 ± 0b	ND	140 ± 18b	104 ± 15	201 ± 14
ifhA::tet							45 ± 6	90 ± 6
narL::cat							102 ± 7	290 ± 14
ldhA::aacC1									4.3 ± 0.7	26 ± 1.8
pta::aacC1									0.4 ± 0.2	0.5 ± 0.2

^aThe results were obtained from microarray experiments and from a ackA-lacZ fusion. The Pta activity in P. aeruginosa wild type and the Δpta and ΔldhA mutants were determined as described in Materials and Methods.

^bObserved signal strength is given in normalized Affymetrix units as defined in Materials and Methods (5, 8). The standard deviation represents the detected differences between the independently performed GeneChip experiments.

^cND, not determined. Because Anr and Dnr activity is known to be limited to anaerobic conditions, analysis of aerobically grown cells was not performed.

^dOne unit of activity is the amount of enzyme that converts 1 μmol of acetyl-CoA to product per 60 min at 30°C.

^eAnaerobic conditions for the microarrays, the reporter gene fusions, and enzyme activity measurements differed depending on the nature of determined parameters. Due to the short half-life of the mRNAs, the RNA for the microarray analysis was prepared 2 h after the shift to anaerobic conditions. Reporter gene fusion expression was determined after 48 h of anaerobic incubation of the culture, while Pta activity was measured after 24 h of fermentative conditions. Employed media, test principles, and given units are defined in Materials and Methods.