Effects of aroL, pncB, and cysJ downstream adenines on expression in vivo. β-Galactosidase activities from aroL-, pncB-, and cysJ-lacZ fusions are compared for cells containing plasmids with and without mutations altering the downstream adenine content (Table 1). (A) Plasmid-free cells and cells containing plasmids with the following aroL-lacZ fusions: pAaroL.WT (100%), pAaroL.DN1 (28%), pAaroL.DN1a (85%), pAaroL.DN1b (56%), and pAaroL.UP1 (138%). (B) Plasmid-free cells and cells containing plasmids with the following pncB-lacZ fusions: pApncB.WT (100%), pApncB.DN1 (0.1%), pApncB.DN1a (11%), pApncB.DN1b (8%), and pApncB.UP1 (33%). (C) Plasmid-free cells and cells containing plasmids with the following cysJ-lacZ fusions: pAZcysJ.WT (100%), pAZcysJ.DN1 (23%), pAZcysJ.Up1 (625%), pAZcysJ.UP1a (274%), and pAZcysJ.UP1b (325%).