A thermostable Gloeophyllum trabeum xylanase with potential for the brewing industry
A thermostable Gloeophyllum trabeum xylanase with potential for the brewing industry
复制标题
一种具有酿造工业潜力的热稳定性 Gloeophyllum trabeum 木聚糖酶
DOI：
10.1016/j.foodchem.2015.12.028
复制
发表时间：
2016-05-15
期刊：
影响因子：
8.8
通讯作者：
Yao, Bin
中科院分区：
文献类型：
--
作者：
Wang, Xiaoyu;Luo, Huiying;Yao, Bin
从密粘褶菌CBS 900.73中克隆了糖苷水解酶家族10的木聚糖酶基因GtXyn 10，并在毕赤酵母GS115中表达。纯化的重组GtXyn 10对木聚糖具有明显的活性（100.0%），地衣（11.2%），葡聚糖（15.2%）和对硝基苯酚-β-纤维二糖（18.6%），在pH 4.5-5.0和75 ℃下表现出最大木聚糖酶和葡聚糖酶活性，在pH 2.0-7.5范围内和在70 ℃下保持稳定性，对胃蛋白酶、胰蛋白酶、大多数金属离子和SDS具有抗性。多重序列比对和模型结构分析确定了GtXyn 10中独特的Gly 48，Gly 48定点突变为Lys将最适温度提高到80 ℃。在模拟糖化条件下，GtXyn 10（80 U）降低糖化醪粘度12.8%，提高过滤速度31.3%。上述所有特性使GtXyn 10对于饲料和酿造行业的潜在应用具有吸引力。(C)2015爱思唯尔有限公司版权所有。
A xylanase gene of glycoside hydrolase family 10, GtXyn10, was cloned from Gloeophyllum trabeum CBS 900.73 and expressed in Pichia pastoris GS115. Purified recombinant GtXyn10 exhibited significant activities to xylan (100.0%), lichenan (11.2%), glucan (15.2%) and p-nitrophenol-beta-cellobiose (18.6%), demonstrated the maximum xylanase and glucanase activities at pH 4.5-5.0 and 75 degrees C, retained stability over the pH range of 2.0-7.5 and at 70 degrees C, and was resistant to pepsin and trypsin, most metal ions and SDS. Multiple sequence alignment and modeled-structure analysis identified a unique Gly48 in GtXyn10, and site-directed mutagenesis of Gly48 to Lys improved the temperature optimum up to 80 degrees C. Under simulated mashing conditions, GtXyn10 (80 U) reduced the mash viscosity by 12.8% and improved the filtration rate by 31.3%. All these properties above make GtXyn10 attractive for potential applications in the feed and brewing industries. (C) 2015 Elsevier Ltd. All rights reserved.