Zhang Zhaokun, Ge Mingyue, Guo Qi, Jiang Yi, Jia Wendi, Gao Le, Hu Jianhua
School of Chemical Engineering, Inner Mongolia University of Technology, Hohhot 010051, China.
Tianjin Key Laboratory for Industrial BioSystems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, No. 32, Xiqi Road, Tianjin Airport Economic Park, Tianjin 300308, China.
J Fungi (Basel). 2022 Mar 22;8(4):325. doi: 10.3390/jof8040325.
A droplet-based microfluidic ultrahigh-throughput screening technology has been developed for the selection of high-β-xylosidase-producing W6 from the atmospheric and room-temperature plasma-mutated library of . β-xylosidase hyperproducers filamentous fungi, W6, exhibited an increase in β-xylosidase activity by 7.1-fold. A novel β-D-xylosidase was purified from the extracellular proteins of W6 and designated as PpBXL. The optimal pH and temperature of PpBXL were 4.0 and 70 °C, respectively. PpBXL had high stability an acidic pH range of 3.0-5.0 and exhibited good thermostability with a thermal denaturation half-life of 10 days at 70 °C. Moreover, PpBXL showed the bifunctional activities of α-L-arabinofuranosidase and β-xylosidase. Supplementation with low-dose PpBXL (100 μg/g substrate) improved the yields of glucose and xylose generated from delignified biomass by 36-45%. The synergism between PpBXL and lignocellulolytic enzymes enhanced delignified biomass saccharification, increased the Xyl/Ara ratio, and decreased the strength of hydrogen bonds.
一种基于液滴的微流控超高通量筛选技术已被开发出来，用于从常压室温等离子体诱变文库中筛选高产β-木糖苷酶的W6。β-木糖苷酶高产丝状真菌W6的β-木糖苷酶活性提高了7.1倍。从W6的胞外蛋白中纯化出一种新型β-D-木糖苷酶，并命名为PpBXL。PpBXL的最适pH和温度分别为4.0和70℃。PpBXL在3.0-5.0的酸性pH范围内具有较高的稳定性，在70℃下热变性半衰期为10天，表现出良好的热稳定性。此外，PpBXL还具有α-L-阿拉伯呋喃糖苷酶和β-木糖苷酶的双功能活性。低剂量PpBXL（100μg/g底物）的添加使脱木质生物质产生的葡萄糖和木糖产量提高了36-45%。PpBXL与木质纤维素分解酶之间的协同作用增强了脱木质生物质的糖化作用，提高了木糖/阿拉伯糖比例，降低了氢键强度。
