使用共有序列设计策略提高嗜热嗜酸β-甘露聚糖酶的催化能力

Improvement of the Catalytic Ability of a Thermostable and Acidophilic β-Mannanase Using a Consensus Sequence Design Strategy.

作者信息

Liang Qingping, Zhan Yuming, Yuan Mingxue, Cao Linyuan, Zhu Changliang, Mou Haijin, Liu Zhemin

机构信息

College of Food Science and Engineering, Ocean University of China, Qingdao, China.

Shandong Provincial Key Laboratory of Quality Safety Monitoring and Risk Assessment for Animal Products, Jinan, China.

出版信息

Front Microbiol. 2021 Sep 1;12:722347. doi: 10.3389/fmicb.2021.722347. eCollection 2021.

In order to improve the catalytic efficiency of a thermostable and acidophilic β-mannanase (ManAK; derived from marine IFO 4308), three mutants were designed by amino acid sequence consensus analysis with a second β-mannanase (ManCbs), which also belongs to the glycoside hydrolase family 5 (GH5) and has excellent catalytic efficiency. Three mutants were constructed and their biochemical characteristics were measured after heterologous expression in . The results revealed that the k/K values of the three recombinant mannanases ManAK, ManAK, and ManAK were enhanced by 303.0, 280.4, and 210.1%, respectively. Furthermore, ManAK showed greater thermostability than ManAK, retaining 36.5% of the initial enzyme activity after incubation at 80°C for 5min. This study therefore provides a rational design strategy based on consensus sequence analysis to develop industrially valuable β-mannanase for future applications in marine aquafeed.

为了提高一种耐热嗜酸β-甘露聚糖酶（ManAK；源自海洋IFO 4308）的催化效率，通过与另一种同样属于糖苷水解酶家族5（GH5）且具有优异催化效率的β-甘露聚糖酶（ManCbs）进行氨基酸序列一致性分析，设计了三个突变体。构建了这三个突变体，并在[具体表达宿主未给出]中进行异源表达后测定了它们的生化特性。结果表明，三种重组甘露聚糖酶ManAK、ManAK和ManAK的k/K值分别提高了303.0%、280.4%和210.1%。此外，ManAK比ManAK表现出更高的热稳定性，在80℃孵育5分钟后仍保留36.5%的初始酶活性。因此，本研究基于一致性序列分析提供了一种合理的设计策略，以开发具有工业价值的β-甘露聚糖酶，供未来在海洋水产饲料中应用。