Figure 7.

(A) Influence of selected metal ions (each at a concentration of 7.5 mM) on the activity of the purified nitrile hydratases (SEC fraction 14 or equivalent; n = 3). (B) Influence of different concentrations of Mn²⁺ on the activity of the purified enzyme (SEC fraction 14 or equivalent; n = 3). The data were analysed assuming a one site binding model, which resulted in an apparent affinity constant of 0.856 ± 0.228 mM for Mn²⁺ ions. The activity is defined as the decrease of substrate (in %) relative to a control without protein. The activity is calculated per 0.1 µg of protein. The error bars are defined as standard deviation.