一色齿毛菌漆酶的酶学特性及染料脱色研究

染料由于具有复杂的化学结构通常难以降解。本文从白腐菌一色齿毛菌LS0547中纯化出胞外漆酶并用于染料脱色实验。SDS-PAGE结果显示纯化的漆酶分子量大小为63.7kDa。漆酶氧化底物ABTS的最适pH为2.2，最适温度为50℃。叠氮钠可强烈抑制漆酶活性，半胱氨酸和二硫苏糖醇可部分抑制漆酶活性。漆酶氧化ABTS，丁香醛连氮和2,6-二甲氧基苯酚的米氏常数分别为0.217，0.306和0.199mmol/L。粗酶和纯化的漆酶用于不同化学结构的染料的脱色研究，结果表明一色齿毛菌纯化漆酶可快速对RB亮蓝进行脱色，偶氮胭脂红和结晶紫的脱色效果低于RB亮蓝，测试的三种染料均可在没有介体存在的条件下被漆酶脱色，显示出一色齿毛菌漆酶在染料废水处理中的应用前景。

Characterization and decolorization ability of a laccase from white rot fungus Cerrena unicolor LS0547

Dyes are usually difficult to be decolorized due to their complex chemical structures. In this work, laccase was purified from the white rot fungus Cerrena unicolor LS0547 to evaluate its application in dye decolorization. SDS-PAGE analysis showed the purified laccase to be a monomeric protein of 63.7kDa. The optimum pH for the oxidation of 2,2'-azinobis-(3-ethylbenzthiaoline-6-sufonic acid) (ABTS) was 2.2 and the optimum temperature was 50℃. The activity of the purified enzyme was strongly inhibited by sodium azide and partially inhibited by cysteine and dithiothreitol. The Km values of the purified laccase for the substrate ABTS, syringaldazine and 2,6-dimethoxyphenol were 0.217, 0.306 and 0.199retool/L, respectively. Chemical different dyes were used in the dye decolorization test. The result indicated that all the dyes could be decoiorized by the crude and purified enzyme in the absence of redox mediators. Remazol brilliant blue R (RBBR) was the most suitable substrate for the laccase from C. unicolor LS0547. Azocarmine B and crystal violet were less decolorized than RBBR. The result demonstrated the potential application prospects of the laccase from C. unicolor in dye-containing wastewater treatment.