Yang Jie, Lin Qi, Ng Tzi Bun, Ye Xiuyun, Lin Juan
College of Biological Sciences and Technology, Fuzhou University, Fuzhou, Fujian, China; National Engineering Laboratory for Enzyme Expression, Fuzhou, Fujian, China.
College of Biological Sciences and Technology, Fuzhou University, Fuzhou, Fujian, China.
PLoS One. 2014 Oct 30;9(10):e110834. doi: 10.1371/journal.pone.0110834. eCollection 2014.
Laccases (EC 1.10.3.2) are a class of multi-copper oxidases with important industrial values. A basidiomycete strain Cerrena sp. HYB07 with high laccase yield was identified. After cultivation in the shaking flask for 4 days, a maximal activity of 210.8 U mL(-1) was attained. A 58.6-kDa laccase (LacA) with 7.2% carbohydrate and a specific activity of 1952.4 U mg(-1) was purified. 2,2'-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) was the optimal substrate, with Km and kcat being 93.4 µM and 2468.0 s(-1), respectively. LacA was stable at 60°C, pH 5.0 and above, and in organic solvents. Metal ions Na+, K+, Ca2+, Mg2+, Mn2+, Zn2+ enhanced LacA activity, while Fe2+ and Li+ inhibited LacA activity. LacA decolorized structurally different dyes and a real textile effluent. Its gene and cDNA sequences were obtained. Putative cis-acting transcriptional response elements were identified in the promoter region. The high production yield and activity, robustness and dye decolorizing capacity make LacA and Cerrena sp. HYB07 potentially useful for industrial and environmental applications such as textile finishing and wastewater treatment.
漆酶（EC 1.10.3.2）是一类具有重要工业价值的多铜氧化酶。鉴定出一株高产漆酶的担子菌菌株Cerrena sp. HYB07。在摇瓶中培养4天后，漆酶的最大活性达到210.8 U mL(-1)。纯化得到一种58.6 kDa的漆酶（LacA），其碳水化合物含量为7.2%，比活性为1952.4 U mg(-1)。2,2'-联氮-双（3-乙基苯并噻唑啉-6-磺酸）是最佳底物，其Km和kcat分别为93.4 µM和2468.0 s(-1)。LacA在60°C、pH 5.0及以上以及有机溶剂中稳定。金属离子Na+、K+、Ca2+、Mg2+、Mn2+、Zn2+增强LacA活性，而Fe2+和Li+抑制LacA活性。LacA可使结构不同的染料和实际纺织废水脱色。获得了其基因和cDNA序列。在启动子区域鉴定出假定的顺式作用转录反应元件。高产率、高活性、稳定性和染料脱色能力使LacA和Cerrena sp. HYB07在纺织整理和废水处理等工业和环境应用中具有潜在用途。
