TABLE 3.

Impact of thioesterases encoded by pchC and pchF on salicylate, Dha, and pyochelin formation in P. aeruginosa^a

Strain	Chromosomal mutation	Plasmids	Genes carried	Salicylate concn (nmol/ml)b	Dha concn (nmol/ml)b	Pyochelin concn (nmol/ml)b
PAO1	Wild type			<8.0	60 ± 4.0	748 ± 25
PAO6331	Δpch			<8.0	<1.2	<2
PAO6331	Δpch	pME6178 + pME6488	entD pchDCBA + pchEFG	256 ± 29	18 ± 2.5	400 ± 74
PAO6331	Δpch	pME6852 + pME6488	entD pchDBA + pchEFG	636 ± 72	5 ± 0.3	120 ± 15
PAO6331	Δpch	pME6178 + pME6886	entD pchDCBA + pchEFC1606A/S1607AG	872 ± 194	81 ± 19.7	<2
PAO6331	Δpch	pME6852 + pME6886	entD pchDBA + pchEFC1606A/S1607AG	757 ± 168	24 ± 1.9	<2

^aGGP medium (30 ml) containing, when required, gentamicin (10 μg/ml) and tetracycline (100 μg/ml) was inoculated with 0.3-ml portions of cultures grown in the same medium. After incubation at 37°C and 220 rpm for 33 h, supernatants were extracted and analyzed for salicylate, Dha, and pyochelin by HPLC. The values are the means ± standard deviations for three parallel experiments.

^bConcentration in culture supernatant.