IMMOBILIZATION AS A TOOL FOR THE STABILIZATION OF LIGNIN PEROXIDASE PRODUCED BY PHANEROCHAETE-CHRYSOSPORIUM INA-12

Lignin peroxidase immobilization was achieved by covalent coupling on CNBr-Sepharose 4B. Protein immobilization yield was around 80%. For veratryl alcohol oxidation, in the presence of hydrogen peroxide, both soluble and bound enzymes exhibited the same pH profile with an optimum near 2.5. Catalytic parameters (kc and K(m)) were seriously affected by immobilization. On the other hand, immobilization provided a noticeable stabilization of the enzyme against acidic pH and high temperatures. A 15-20 increase in the half-inactivation times at pH 2.2 and 2.7, respectively, could be observed. Bound enzyme was also much more thermostable than soluble.