TABLE 2.

β-Galactosidase fusion analysis of the native dctA promoter

Strain	Genotype	Fusiona	β-Galactosidase activity under the following growth conditionb:
			Glc-NH4	Succ-NH4	Glc-Asp	Succ-Asp	Glc-Succ-NH4	Glc-Succ-Asp	Glc-Asp-NH4	Succ-Asp-NH4
3841	Wild type	dctA-lacZ	266 ± 61	2,067 ± 267	1,533 ± 356	3,433 ± 101	2,228 ± 257	3,997 ± 273	1,944 ± 128	1,751 ± 253
RU150	dctA101	dctA-lacZ	148 ± 28		2,223 ± 120	1,251 ± 73
RU727	dctA::Ω	dctA-lacZ	297 ± 25		3,417 ± 248		2,073 ± 212	3,396 ± 354	2,558 ± 341
RU730	dctB::Ω	dctA-lacZ	184 ± 27		273 ± 36		102 ± 20	237 ± 112	102 ± 33
RU711	dctD::Ω	dctA-lacZ	150 ± 26		235 ± 6		91 ± 5	198 ± 35	136 ± 47
RU865	ΔdctBD::Ω	dctA-lacZ	168 ± 10		255 ± 61		141 ± 53	460 ± 157	210 ± 73
RU714	ΔdctABD::Ω	dctA-lacZ	179 ± 65		264 ± 46		205 ± 50	380 ± 122	161 ± 35
RU436	dctA::Tn5	dctA-lacZ	286 ± 12		2,945 ± 123		2,407 ± 122	4,080 ± 147	1,886 ± 58
RU437	dctA::Tn5	dctA-lacZ	230 ± 37		3,078 ± 369		3,057 ± 107	4,475 ± 143	2,281 ± 165
3855	Wild type	dctA-lacZ	260 ± 45		1,620 ± 75		1,960 ± 104
CR534	dctA::Tn5	dctA-lacZ	315 ± 85		2,755 ± 84		3,119 ± 123
CR535	dctB::Tn5	dctA-lacZ	113 ± 12		95 ± 3		97 ± 12
CR538	dctD::Tn5	dctA-lacZ	111 ± 21		120 ± 12		111 ± 23
3841	Wild type	pMP220	120 ± 40	168 ± 21	180 ± 42	205 ± 62

^aThe dctA-lacZ fusion is pRU103; the vector control is pMP220. 

^bResults are shown as o-nitrophenylgalactoside hydrolyzed (in nanomoles per minute per milligram of protein ± SEM) and are based on at least three independent cultures assayed in triplicate. Glc, glucose; Succ, succinate; Asp, aspartate. All growth substrates were used at 10 mM concentrations.