TABLE 3.

Expression from the Phmg promoter is controlled by HmgR^a

E. coli strain	Plasmid	Relevant background	β-Galactosidase activity (Miller units)
			Uninduced	Phe	Tyr	4-OH-PhPyr	2,5-OH-PhAc	2,5-OH-benzoate
AF141	None	lacZ	NDb	ND	ND	ND	ND	ND
BMR	None	Phmg-lacZ	2,520	2,462	2,347	2,269	2,017	2,303
BMR	pQE32	Phmg-lacZ	1,890	1,895	1,912	1,425	1,343	1,593
BMR	pQ-hmgR	Phmg-lacZ hmgR	9	15	14	27	1,047	198

^aE. coli strains were grown in glycerol-containing MM in the absence (uninduced) or in the presence of 5 mM Phe, Tyr, 4-OH-PhPyr, 2,5-OH-PhAc (homogentisate), or 2,5-OH-benzoate (gentisate). β-Galactosidase activities were measured with permeabilized cells as described in Materials and Methods.

^bND, not detected.