TABLE 1.

Expression of uhpT promoter variants and the effect of presence of UhpA and the CAP-binding site

uhpTplacZd	β-Galactosidase activity in indicated host strain when uhpT-lacZ fusion is carried one:
	Plasmida				Lysogenb
	RK1280 uhp+		RK1271 ΔuhpA		RK1280 uhp+		RK1271 ΔuhpA		RK1280 ΔCAP sitec
	−	+	−	+	−	+	−	+	−	+
None	2	1	2	2	1	1	1	2	1	1
WTg	42	1,790	3	3	2	387	1	1	1	31
Ω10	5	3	5	4	1	1	1	1	1	1
Ω1	2	385	2	7	1	45	NDf	ND	3	5
Δ1	17	145	6	6	1	75	ND	ND	1	1
Δ10	5	13	5	4	1	3	1	1	1	1
Δ11	21	65	20	22	2	4	ND	ND	1	1
Δ20	123	545	96	96	5	37	13	13	2	8
Δ21	207	1,650	117	121	126	139	19	22	1	3
Δ22	232	885	194	200	232	313	85	93	1	1
Δ22 Ω22	52	70	53	54	22	26	4	4	ND	ND
Nu35	4,360	4,480	4,780	5,010	1,390	1,550	1,765	1,870	ND	ND

^aThe indicated promoter variants were inserted at the EcoRI-BamHI fragment upstream of the promoterless lacZ gene in plasmid pRS415. Plasmids were introduced by transformation into strains RK1280 (uhp⁺) and RK1271 (ΔuhpA), as indicated. 

^bThe uhpT promoter variants were transferred from plasmid pRS415 derivative to λRZ5 by homologous recombination, and phage lysates were used to isolate ampicillin-resistant lysogens in the indicated host strains. Single lysogens were used. 

^cThe series of uhpT promoter variants were subjected to a second round of PCR-based mutagenesis in which the CAP recognition sequence was altered by seven base changes. 

^dThe sequence changes in the promoter variants are indicated in Fig. 2. 

^eThe β-galactosidase activity was measured in triplicate in at least three independent experiments. Cells were grown in the absence (+) or presence (−) of 0.25 mM Glu6P as indicated and assayed in a microplate reader (Molecular Devices, Inc.). 

^fND, not determined. 

^gWT, wild type.