The optimum temperature for activity was also increased after enzyme immobilization (Fig. 2A). The free enzyme presented the highest activity at 50◦C; however, the immobilized enzyme presented maximum activity at 60◦C, maintaining a high activity even up to 80◦C (at this temperature the free enzyme was almost inactive). Fig. 2B shows that the enzyme was actually more stable than the free enzyme at 60◦C, and that may be the explanation for this improved features found in the immobilized enzyme. After 12 h of incubation, the immobilized derivative retained about 60% activity,whilst the free form retained just 30% activity (Fig. 2B). The time needed to reach 50% of residual activity was about 3 h for the free enzyme and about 19 h for immobilized preparation. Rigidification of the enzyme structure via multipoint attachment and reduction of dissociation problems via multisubunit immobilization are the likeliest explanations, for these good results.