TABLE 1.

Bacterial strains and plasmids

Strains or plasmid	Genotype or properties	Source or reference
Strains
MC4100	araD139 Δ(argF-lac)U169 rpsL150 relA1 flbB5301 ptsF25 deoC1	3
RH74	MC4100 Δcya851 ilv::Tn10	20
SBS688	MC4100 Δcrp39	13
DH5α	thi-1 hsdR17 gyrA96 recA1 endA1 glnV44 relA1 φ80dlacZΔM15 phoA8	NCCB
Plasmids
pRK100	F-like plasmid	1
pCB267	lacZ promoter probe vector	28
pTJ1	pCB267; 210-bp traJ promoter insert	This study
pGEM-T Easy	T-vector for cloning of PCR products	Promega
pUC19	Multipurpose cloning vector	33
pINP2	PGEM-T Easy; 158-bp ΔlacZ insert	This study
pYZCRP	CRP encoding	R. H. Ebright