Purification of a novel extracellular laccase from solid-state culture of the edible mushroom <Emphasis Type="Italic">Lentinula edodes</Emphasis>

The laccases (EC 1.10.3.2) secreted into solid-state culture by Lentinula edodes were analyzed. The fungus secreted at least two laccases in the solid-state culture. One laccase was purified to a homogeneous preparation using anion-exchange, hydrophobic, and size-exclusion chromatography. SDS-PAGE analysis showed that the purified laccase, Lcc6, was a monomeric protein of 58.5 kDa. The optimum pH for enzyme activity was about 3.5, and the laccase was most active at 40°C. The N-terminal amino acid sequence of Lcc6 did not correspond to the sequence of Lcc1, which was previously purified from L. edodes. Lcc6 had decolorization activity to some chemical dyes.