FIGURE 3.
Effects of overexpression of full-length and SKK domain of NusA on the in vivo transcription. β-Galactosidase activities from the lacZ reporter fused downstream of Rho-dependent terminators, H-19B tR1 (A and C) and trac (B and D). The effects of overexpression of different derivatives of full-length (FL) NusA (A and B) and its SKK fragment (C and D) are shown. Concentrations of these two species were varied by adding (+) or omitting (−) 0.1% glucose (Glu) as they were expressed from the PBAD promoter. In vivo levels of full-length NusA and SKK fragments were verified by Western blotting (data not shown). Because the in vivo levels of different NusA derivatives were similar (∼3-fold enhancement upon induction), we did not attempt to normalize the β-galactosidase activities. S.D. values (error bars) were obtained from five independent measurements. vector, empty plasmid without the nusA. A.U., arbitrary units.