FIG. 2.

Stability of native T. versicolor laccase at different pH values. Laccase was incubated for 24 h at 22°C in the following buffers (concentrations, 50 mM): glycine-HCl (pH 2.4, 3.0, and 3.4), sodium acetate (pH 4.0 and 5.0), phosphate (pH 6.0, 7.0, and 8.0), and glycine-NaOH (pH 9.0). After incubation, the activity at pH 5.2 was determined by using ABTS as the reducing substrate.