Immobilization of metapyrocatechase and its properties in comparison with the soluble enzyme.

Metapyrocatechase [catechol : oxygen 2,3-oxidoreductase, EC 1.13.11.2] was immobilized with cyanogen bromide-activated agarose with a coupling yield of 78% of the protein added. The immobilized enzyme showed a specific activity of 77 mumol/min/mg protein, which is about 30% of that of the native enzyme. The immobilization enhanced the stability of the enzyme against inactivation by heat, acid or alkaline pH, and various denaturing agents. However, like the native enzyme, the immobilized enzyme was rapidly inactivated by oxidants such as oxygen or hydrogen peroxide, and the inactivation was completely prevented in the presence of low concentrations of organic solvents. The pH profile for the activity and the substrate specificity were slightly changed by the immobilization.