Figure 5. Induction of β-lactamase synthesis in presence (induced) or not (non-induced) of inducer (2.5 µg ml⁻¹ cephalosporin C) for the B. subtilis strains transformed with pDML995 (wild-type divergeon; •) or pDML3045 (mutation R³⁰⁴A/R³⁰⁵A;○).

The level of the induction is expressed as an induction factor (IF, the ratio between the β-lactamase quantity/A⁶⁰⁰ for induced culture and the β-lactamase quantity/A⁶⁰⁰ for uninduced culture).