FIG. 3.

Nucleotide sequences of the operator region of the wild type and mutants isolated by site-directed mutagenesis and mutagenic PCR. Underlining indicates the palindrome. For mutants, only the mutant nucleotides are shown. Fragments containing the control region with either wild-type sequence or with the indicated mutations were fused to lacZ in pDG268 and integrated into the amyE locus. β-Galactosidase activity is shown for succinate-grown cells. Enzyme levels of XM15 were taken from Fig. 1. The inducer dRib was added to a final concentration of 1 mg/ml.