FIG. 2.

Expression of a chromosomal benA::lacZ fusion in strains encoding CatM or variant regulators [CatM(V158M), encoded by catM5153, or CatM(R156H), encoded by catM3102]. All strains lack a functional benM, and two strains have a point mutation at position −40 relative to the benA transcription initiation site (benMA5146) (see Fig. 1). Cultures were grown on succinate or muconate as indicated. β-Galactosidase (LacZ) activity is shown relative to that measured for succinate-grown ACN47 (6.9 μmol/min/ml/OD₆₀₀). Activities are averages of at least four repetitions, and standard deviations were <20% of the average value.