Manganese peroxidase (MnP) purified from commercial cultures of Lentinula edodes was covalently immobilized through its carboxyl groups using an azlactone-functional copolymer derivatized with ethylenediamine and 2-ethoxy-1-ethoxycarbonyl-1,2-dihydroquinoline (EEDQ) as a coupling reagent. The tethered enzyme was employed in a two-stage immobilized MnP bioreactor for catalytic generation of chelated Mn-III and subsequent oxidation of chlorophenols. Manganese peroxidase immobilized in the enzyme reactor (reactor 1) produced Mn-III-chelate, which was pumped into another chemical reaction vessel (reactor 2) containing the organopollutant. Reactor 1-generated Mn-III-chelates oxidized 2,4-dichlorophenol and 2,4,6-trichlorophenol in reactor 2, demonstrating a two-stage enzyme and chemical system. H2O2 and oxalate chelator concentrations were varied to optimize the immobilized MnP's oxidation of Mn-II to Mn-III. Oxidation of 1.0 mM Mn-II to Mn-III was initially measured at 78% efficiency under optimized conditions. After 24 h of continuous operation under optimized reaction conditions, the reactor still oxidized 1.0 mM Mn-II to Mn-III with similar to 69% efficiency, corresponding to 88% of the initial MnP activity.