TABLE 1.

Expression of alsS-lacZ fusion in ccpA mutants^a

Strain	ccpA allele	β-Galactosidase activity		Ratio
		− Glucose	+ Glucose
ZB449Tn2CWT	Wild type	0.77	35	45
CM18AV	ccpA18AV	0.63	1.0	1.6
CM48RC	ccpA48RC	0.63	1.6	2.5
CM286PL	ccpA286PL	0.65	0.94	1.5
ZB449ccpTn2	ccpA::spc	0.66	0.73	1.1

^aAll strains contained the Tn2 alsS::Tn917lac insertion (21). Cells were grown in TSS medium (4) containing 1% Casamino Acids (− glucose) or TSS medium containing 1% Casamino Acids and 1% glucose (+ glucose). β-Galactosidase activities are expressed in Miller units (13) and indicate activity 2 h after the time of entry of the culture into stationary phase. The ratio indicates the level of induction during growth in the presence of glucose. All growth experiments were carried out at least twice, and samples were assayed in duplicate; variation was less than 10%.