Table 2.

Effect of d- or l-arginine on dauB and dauT promoter activities in PAO1

Plasmid (promoter)	C & N source	Specific activities, nmol/min per mg*
pCR1 (dauB)	Glu	34
	Glu + d-arg	680
	Glu + l-arg	63
pZY4 (dauT) (7)	Glu	619
	Glu + d-arg	6006
	Glu + l-arg	233

C & N, carbon and nitrogen; Glu, cells were grown in MMP-glutamate; Glu + d-arg, cells were grown in MMP-glutamate supplemented with 5 mM d-arginine; and Glu + l-arg, cells were grown in MMP-glutamate supplemented with 20 mM l-arginine.

*Specific activities of β-galactosidase expressed from plasmids were averages of 2 measurements for each growth condition, with standard errors of less than 5%.