Purification and characterization of laccase from the rice blast fungus, Magnaporthe grisea

A 70-kDa extracellular laccase was purified from the rice blast fungus Magnaporthe grisea using gel filtration and ion exchange chromatography The procedure provided 282-fold purification with a specific enzyme activity of 225.91 U mg(-1) and a yield of 11.92%. The enzyme oxidized a wide range of substrates. The highest level of oxidation was detected with syringaldazine as the substrate. Using syringaldazine as the substrate, the enzyme exhibited a pH optimum of 6 and temperature optimum of 30degreesC, and its K-m was 0.118 mM. The enzyme was strongly inhibited by Cu-chelating agents. (C) 2003 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved.