TABLE 3.

Interoperator spacing influences O3-napF enhancement of NarL-mediated repression at O1-napF

Strain	Construct	Spacinga	Genotype		LacZ sp act (arbitrary units)b		Repression (fold)
			narL	narP	No NO3−	NO3−
VJS8880	O3-lac O1-napF	91	+	+	1,190	100	12
VJS8882	O3-lac O1-napF	91	+	−	1,170	110	11
VJS8881	O3-lac O1-napF	91	−	+	1,020	140	7.3
VJS9004	O3-lac O1-napF	91	−	−	1,010	650	1.6
VJS8883	O3-napF O1-napF	91	+	+	1,150	55	21
VJS8885	O3-napF O1-napF	91	+	−	1,200	35	34
VJS8884	O3-napF O1-napF	91	−	+	1,100	130	8.5
VJS9005	O3-napF O1-napF	91	−	−	1,100	720	1.5
VJS8899	O3-napF O1-napF	87	+	+	870	23	38
VJS9001	O3-napF O1-napF	87	+	−	980	17	58
VJS9000	O3-napF O1-napF	87	−	+	1,100	100	11
VJS9006	O3-napF O1-napF	87	−	−	970	620	1.6

^aInteroperator spacing (see Fig. 1).

^bStrains were cultured overnight in MOPS defined medium with limiting glucose.