杏鲍菇漆酶部分酶学性质的研究  

Studies on Partial Enzymatic Properties of Laccase from Pleurotus eryngii

作　　者：万善霞[1] 滑静[1] 王文平[1] 张淑萍[1] 

机构地区：[1]北京农学院生物技术系,北京102206

出　　处：《中国农学通报》2009年第21期107-109,共3页Chinese Agricultural Science Bulletin

基　　金：北京市教委资助项目"固定化杏鲍菇漆酶处理工业废水的研究"(KM200710020010)

摘　　要：漆酶是一种含铜多酚氧化酶,可以氧化分解各种酚类染料、芳香胺等,由于漆酶具有相当宽泛的底物专一性和较好的稳定性,漆酶在废水处理、生物漂白、芳香化合物转化、生物传感器构建等方面具有重要应用价值。从多种新鲜食用菌子实体中提取漆酶,发现杏鲍菇漆酶的酶活性最高,对其酶学性质的研究对今后漆酶的应用提供有价值的理论数据。漆酶提取液通过硫酸铵分级沉淀、透析制备漆酶粗酶液。采用分光光度法,以ABTS[2,2′-Azino-bis（3-ethylbenzothiazoline-6-sulfonic acid）]为底物测定漆酶活力。结果表明,杏鲍菇漆酶的最适反应温度为45℃。该酶在50℃以下保温1-4h,酶活损失很小,但当温度超过70℃时,酶活力损失较大。但漆酶的贮存稳定性相对较高,酶液在4℃下保存近60天后仍残留60%的酶活性。杏鲍菇漆酶的最适pH为3.0;漆酶在pH4.0-8.0,25℃保温1-10h酶活力损失15%-25%,但在pH2.0-3.6,25℃保温1-10h酶活力损失40%-60%。金属离子对漆酶活性有明显的影响作用,Ca^2＋、Mn^2＋、Fe^2＋、Ag^＋对酶的活性有抑制作用,Na^＋、K^＋、Mg^2＋、Cu^2＋、Pb^2＋、Zn^2＋对酶的活性有促进作用。从上述实验结果可以得出结论：杏鲍菇漆酶在50℃以下保温，相对酶活性及热稳定性均较好。最适温度为45℃。但当温度超过70℃时，酶活性被强烈抑制。杏鲍菇漆酶的最适pH为3．0，表明该酶可以在较酸的环境中发挥作用。金属离子作为酶的辅助因子可以激活或抑制漆酶的活性。The laccase as a copper-containing polyphenol oxidase, can oxidise a variety of phenolic oxidation dyes, aromatic amines, etc. as a result of its broad substrate specificity and good stability, laccase is used in wastewater treatment, biobleaching to build an important application value. The laccase was extracted from fresh Pleurotus eryngi fruit body. Crude laccase extraction was through ammonium sulfate fractional precipitation, dialysis Preparation. The laccase activity was determined by spectrophotometry.The results showed that optimal temperature of laccase was 45 ℃. It was preserved below 50 ℃ for 1-4 h, the activity loss is very small, but when the temperature exceeds 70 ℃, a larger loss of enzyme activity was found. The optimal pH of laccase was 3.0. Laccase was insulated at 25 ℃ in pH 4.0-8.0 for 1-10 h, laccase activity was lose by 15%-25%, but in pH 2.0-3.6, by 40%-60%. The activity was inhibited by Ca^2＋. Mn^2＋. Fe^3＋. Ag^＋, and was enhanced by Na^＋, K^＋, Mg^2＋, Cu^2＋, Pb^2＋, Zn^2＋. From the above results it can be concluded： The laccase was insulated below 50 ℃, the relative activity and thermal stability was good. The optimal temperature was 45 ℃. The optimal pH was 3.0. Metal ions as a cofactor of enzymes can activate or inhibit the activity of laccase.

关 键 词：杏鲍菇 漆酶 酶学性质 

分 类 号：Q554.9[生物学—生物化学]