Catalytic activity of mesoporous silicate-immobilized chloroperoxidase

A versatile enzyme, FeHeme chloroperoxidase (CPO) from Caldariomyces fumago, is immobilized in the mesoporous silicate material, mesocellular foam (MCF). MCF is a promising material for immobilizing enzymes, due to its large pore structure and high loading capacity compared to other mesoporous materials, such as MCM-48, SBA-16 and SBA-15. The immobilized CPO in MCF retains its activity. The optimal pH at which the maximum amount of enzyme is immobilized was determined to be pH 3.4, slightly below the isoelectric point of the enzyme. A weak ionic interaction between the enzyme and the surface of the inorganic substrate is thought to be critical in maintaining the activity of the immobilized enzyme. The loading capacity of MCF is 122 mg protein per 1 g of MCF. We demonstrate the advantage of MCF as an inorganic substrate for immobilization of enzymes.