Institute of Microbiology, Beijing Forestry University, Beijing 100083, China.
Bioresour Technol. 2013 Jan;128:49-57. doi: 10.1016/j.biortech.2012.10.085. Epub 2012 Oct 29.
Extracellular laccase (Tplac) from Trametes pubescens was purified to homogeneity by a three-step method, which resulted in a high specific activity of 18.543 Umg(-1), 16.016-fold greater than that of crude enzyme at the same level. Tplac is a monomeric protein that has a molecular mass of 68 kDa. The enzyme demonstrated high activity toward 1.0mM ABTS at an optimum pH of 5.0 and temperature of 50 °C, and under these conditions, the catalytic efficiency (k(cat)/K(m)) is 8.34 s(-1) μM(-1). Tplac is highly stable and resistant under alkaline conditions, with pH values ranging from 7.0 to 10.0. Interestingly, above 88% of initial enzyme activity was maintained in the presence of metal ions at 25.0mM, leading to an increase in substrate affinity, which indicated that the laccase is highly metal-tolerant. These unusual properties demonstrated that the new fungal laccase Tplac has potentials for the specific industrial or environmental applications.
从长毛栓菌中提取的胞外漆酶（Tplac）经过三步纯化法达到了均一性，其比活力达到 18.543 Umg(-1)，比同水平的粗酶提高了 16.016 倍。Tplac 是一种单体蛋白，分子量为 68 kDa。该酶在 pH 值为 5.0、温度为 50°C 的最佳条件下对 1.0mM ABTS 表现出高活性，在这些条件下，催化效率（k(cat)/K(m)）为 8.34 s(-1) μM(-1)。Tplac 在碱性条件下高度稳定且耐受，pH 值范围为 7.0 至 10.0。有趣的是，在 25.0mM 金属离子存在的情况下，初始酶活性仍保持在 88%以上，这导致了底物亲和力的增加，表明该漆酶具有较高的耐金属性。这些不寻常的特性表明，新型真菌漆酶 Tplac 具有在特定工业或环境应用中的潜力。
