FIG. 7.

(A) Constructs of fsrA, fsrB, and gelE promoter lacZ fusions. DNA fragments (boxes) containing putative fsrA, fsrB, and gelE promoters were cloned in front of a promoterless lacZ in shuttle vector pTCV-lac, resulting in plasmids pTEX5268 (putative fsrA promoter in pTCV-lac), pTEX5269 (putative fsrB promoter in pTCV-lac), and pTEX5270 (putative gelE promoter in pTCV-lac), respectively. The distances of each end of the fragments from fsrA, fsrB, and gelE start codons are indicated. (B) Determination of fsrA, fsrB, and gelE promoter activities of lacZ fusion constructs in OG1RF. The β-galactosidase activity assay was performed as described in Materials and Methods. β-Galactosidase activity was represented as units per unit of optical density at 600 nm (OD₆₀₀) of cells per minute. Error bars, standard deviations.