TABLE 2.

Induction of QR by various aromatic compounds^a

Inducer	Concn (mM)	Induction (fold)b
Quinones
p-Benzoquinone	0.2	12
MBQ	0.2	12
DMBQ	0.2	12
1,4-Naphthaquinone	0.2	10
3,5-Di-tert-buryl-1,2-orthoquinone	0.2	1.3
2-Chloroquinone	0.2	2.2
Hydroquinones
p-Hydroquinone	0.2	6.8
2-Methoxyhydroquinone	0.2	11
2,6-Dimethoxyhydroquinone	0.2	11
Aromatic acids
Benzoic acid	2.0	1
p-Hydroxybenzoic acid	2.0	8.8
Vanillic acid	2.0	25
3,4-Dihydroxybenzoic acid	2.0	1.4
3,5-Dihydroxybenzoic acid	2.0	1
Syringic acid	2.0	1.3
Ferulic acid	2.0	28
Veratic acid	2.0	4.0
Aromatic aldehyde
Vanillyl aldehyde	2.0	15
Aromatic alcohols
Veratryl alcohol	2.0	1
Vanillyl alcohol	2.0	1
Phenols
Phenol	0.2	1
4-Chlorophenol	0.2	7.3
2,4-Dichlorophenol	0.2	1
2,6-Dichlorophenol	0.2	2.2
2,6-Dichlorophenol	0.2	2.0
3,4-Dichlorophenol	0.2	1.9
3,5-Dichlorophenol	0.2	1
2,4,5-Trichlorophenol	0.2	1.9
2,4,6-Trichlorophenol	0.2	1
Pentachlorophenol	0.2	1
Nitroaromatic compounds
Nitrobenzene	0.2	1
2-Nitrophenol	0.2	5.7
4-Nitrophenol	0.2	1.8
2,4-Dinitrobenzoic acid	0.2	1
3,5-Dinitrobenzoic acid	0.2	1
2,4-Dinitrotoluene	0.2	1
2,6-Dinitrotoluene	0.2	1
4-Nitrocatechol	0.2	1
2,4,6-Trinitrotoluene	0.2	2.2

^aCells were grown for 2 days in HN medium, and then compounds were added as described in the text; 16 h after the compounds were added, cells were harvested and broken, and the enzyme was assayed as described in the test. 

^bThe level of induction was determined by dividing the specific activity of an induced culture by the specific activity of the uninduced control.