Department of Biology and Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong SAR, PR China.
Bioresour Technol. 2010 Dec;101(24):9772-7. doi: 10.1016/j.biortech.2010.07.091. Epub 2010 Jul 27.
An extracellular laccase was purified from the culture medium of the non-white rot, anthracene-degrading fungal strain Fusarium solani MAS2. Both native PAGE and SDS-PAGE revealed one single band corresponding to a molecular weight of about 72 kDa. Treatment with endoglycosidase H reduced the molecular weight by 12%. The purified laccase maintained stable at pH 3-11 and up to 50 degrees C. The highest activity was detected at pH 3.0 and at 70 degrees C. The enzyme retained 46.2-97.2% of it activity in the presence of 20mM Pb(2+), Ni(2+), Cr(3+), and its activity was enhanced in the presence of 20mM Hg(2+). The laccase retained more than 50% of its activity in the presence of 5% acetone, acetonitrile, dimethyl sulphoxide (DMSO), ethanol and methanol. The kinetic constants (K(m) and k(cat)) showed that 2,6-dimethoxyphenol (DMOP) and 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) diammonium salt (ABTS) were the more effective substrates rather than catechol and guaiacol. The novel properties of this laccase suggest its potential for biotechnological and environmental applications.
从非白腐菌、蒽降解真菌菌株尖孢镰刀菌 MAS2 的培养基中纯化出一种细胞外漆酶。天然 PAGE 和 SDS-PAGE 均显示出一条单一的带，分子量约为 72 kDa。用内切糖苷酶 H 处理后，分子量降低了 12%。纯化的漆酶在 pH 3-11 和高达 50°C 的温度下保持稳定。在 pH 3.0 和 70°C 时，酶的活性最高。该酶在 20mM Pb(2+)、Ni(2+)、Cr(3+)存在下保留了 46.2-97.2%的活性，在 20mM Hg(2+)存在下活性增强。漆酶在 5%丙酮、乙腈、二甲基亚砜（DMSO）、乙醇和甲醇存在下保留了超过 50%的活性。动力学常数（K(m)和 k(cat)）表明，2,6-二甲氧基苯酚（DMOP）和 2,2'-联氮双（3-乙基苯并噻唑啉-6-磺酸）二铵盐（ABTS）是更有效的底物，而不是儿茶酚和愈创木酚。该漆酶的新特性表明其在生物技术和环境应用方面具有潜力。
