TABLE 2.

β-Galactosidase expression with fusions of the wild-type ttgG promoter or single-point ttgG mutant promoters to ′lacZ^a

Location and base changed	β-Galactosidase activityb
	−Toluene	+Toluene
Wild type	290	700
T-16→A	280	725
T-13→A	5	10
T-13→G	10	10
T-13→C	2	2
A-12→C	10	8
A-12→G	7	10
A-12→T	10	15
C-11→A	570	610
C-11→T	2,755	3,360
A-10→C	130	235
A-10→G	70	150
C-9→A	1,690	2,700
C-9→G	68	180
C-9→T	175	390
T-8→A	10	30
T-8→G	10	22
T-8→C	3	4
C-7→G	15	30
C-7→T	180	465
T-6→A	15	40
T-6→C	455	1,100
T-6→G	460	1,080
A-5→C	265	710
C-4→A	1,410	1,560
C-4→G	1,580	1,825
C-3→G	1,570	1,820

^aP. putida DOT-T1E bearing pANA96 (P_ttgG::′lacZ) or pMEx bearing a fusion of the indicated mutant P_ttgG promoter to ′lacZ were grown on Luria-Bertani medium with tetracycline in the absence or presence of 3 mM toluene. After 4 h of incubation, the β-galactosidase activity (Miller units) in permeabilized cells was determined in triplicate (3).

^bValues are the average of three to five independent duplicate assays. Standard deviations were below 10% of the given values.