The Optimization Production, Purification And Properties Of Manganese Peroxidase From Trametes Versicolor

The basidiomycete Trametes versicolor is a kind of white-rot fungus and the manganese peroxidase (MnP) from it is a potent degrader of lignin.Different culture conditions of manganese peroxidase from Trametes versicolor were investigated. The highest level of activity was observed after 7 days when the pH was 4.5 and the incubation temperature was 30 ℃. A noteworthy finding was that fructose was the best carbon source, which was different from the reports that glucose was the best one. The concentration of Mn2+ had no significant influence on manganese peroxidase production and the addition of Tween80 increased the production of manganese peroxidase obviously.Two manganese peroxidase isozymes (MnP1 and MnP2) were purified from the liquid cultures of Trametes versicolor.The proteins were purified to electrophoretic homogeneity using ammonium sulfate precipitation, DEAE-cellulose DE52 chromatography, Phenyl Sepharose TM 6 Fast Flow chromatography and Sephacryl S-200HR chromatography. Their specific activities were 579.09U/mg and 425.00U/mg; purification folds were 17.51 and 12.85 and the yields were 6.17% and 2.47 % .respectively. Both isoenzymes had approximate molecular masses as determined by SDS-PAGE, 46.3KDa for MnPl and 43.0KDa for MnP2.MnP1 and MnP2 differed in optimum pH (5.8 and 6.2) and optimum temperature (60℃ and 65℃) for oxidation of DMP (2,6-dimethoxyphenol). MnPl and MnP2 were stable below 45℃ and from pH4.0 to pH7.0. DMP was the best substrate, the Km values of MnPl and MnP2 for DMP were 13.43μmol/L and 12.45μmol/L respectively. Catalysis didn't occurred in the complete absence of Mn2+. EDTA inhibited the activities of MnPl and MnP2 at the higher concentration and DTT inhibited the enzyme activities completely.