Figure 6

The alkalistability (a) and thermostability (b) of PelN. (a) The pH-dependent stability was determined by incubation at 45°C for 60 min in 50 mM sodium citrate–citric acid buffer (pH 4.0–6.6, ●), 50 mM Tris–HCl buffer (pH 6.6–9.2, ○), 50 mM glycine–NaOH buffer (pH 9.2–11.0, ■), and 50 mM Na₂HPO₄–NaOH buffer (pH 11.0–12.0, □); (b) Thermostability was determined by incubation at 45°C (●), 50°C (○), 55°C (▲), and 60°C (△), respectively. The measured specific activity of PelN without treatment was used as reference (100%), and all reactions were performed under the standard conditions. Error bars represent ± SD (n = 4).