Key Laboratory of Marine Genetics and Breeding (Ocean University of China), Ministry of Education, Yushan Road, No. 5, Qingdao, China.
Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Shi, 266003, Shandong Sheng, Qingdao, China.
Mar Biotechnol (NY). 2019 Feb;21(1):76-87. doi: 10.1007/s10126-018-9860-2. Epub 2018 Nov 19.
Aureobasidium melanogenum strain 11-1 with a high laccase activity was isolated from a mangrove ecosystem. Under the optimal conditions, the 11-1 strain yielded the highest laccase activity up to 3120.0 ± 170 mU/ml (1.2 U/mg protein) within 5 days. A laccase gene (LAC1) of the yeast strain 11-1 contained two introns and encoded a protein with 570 amino acids and four conserved copper-binding domains typical of the fungal laccase. Expression of the LAC1 gene in the yeast strain 11-1 made a recombinant yeast strain produce the laccase activity of 6005 ± 140 mU/ml. The molecular weight of the recombinant laccase after removing the sugar was about 62.5 kDa. The optimal temperature and pH of the recombinant laccase were 40 °C and 3.2, respectively, and it was stable at a temperature less than 25 °C. The laccase was inhibited in the presence of sodium dodecyl sulfate (SDS), ethylenediaminetetraacetic acid (EDTA), phenylmethanesulfonyl fluoride (PMSF), and DL-dithiothreitol (DTT). The K and V values of the laccase for 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) was 6.3 × 10 mM and 177.4 M/min, respectively. Many synthetic dyes were greatly decolored by the laccase.
从红树林生态系统中分离到一株产漆酶活力较高的嗜热枝孢菌（Aureobasidium melanogenum）11-1 菌株。在最佳条件下，该菌株在 5 天内产生的漆酶活力最高可达 3120.0±170 mU/ml（1.2 U/mg 蛋白）。酵母菌株 11-1 的漆酶基因（LAC1）含有两个内含子，编码一个含有 570 个氨基酸的蛋白质，具有真菌漆酶典型的四个保守铜结合域。LAC1 基因在酵母菌株 11-1 中的表达使重组酵母菌株产生的漆酶活力达到 6005±140 mU/ml。去除糖后，重组漆酶的分子量约为 62.5 kDa。重组漆酶的最适温度和 pH 分别为 40°C 和 3.2，在低于 25°C 的温度下稳定。该漆酶在存在十二烷基硫酸钠（SDS）、乙二胺四乙酸（EDTA）、苯甲基磺酰氟（PMSF）和二硫苏糖醇（DTT）时受到抑制。漆酶对 2,2-联氮-双（3-乙基苯并噻唑啉-6-磺酸）（ABTS）的 K 和 V 值分别为 6.3×10 mM 和 177.4 M/min。许多合成染料被该漆酶大大脱色。
