来自Acetivibrio热细胞的核糖5-酸盐异构酶B的突变和结构分析:转化效率和基质结合口袋形状之间的关系
Shitong Dong1, Yuanwei Wang1, Han Zhao1
1State Key Laboratory of Green Papermaking and Resource Recycling, Qilu University of Technology (Shandong Academy of Science), Jinan 250353, PR China; Shandong Provincial Key Laboratory of Microbial Engineering, Department of Bioengineering, Qilu University of Technology (Shandong Academy of Science), Jinan 250353, PR China.
Enzyme and microbial technology
|June 15, 2025
概括
研究人员通过设计酶Ribose 5-phosphate isomerase (RPI) 来增强罕见的糖D-allose的生产. 特定突变显著增加了酶活性和稳定性,实现了迄今为止最高的D-酸转化率.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 代谢工程是代谢工程.
背景情况:
- 糖是一种罕见的糖糖,在食品和医药方面具有显著的潜力.
- 核糖5-酸盐异构酶 (RPI) 对于D-合物合成至关重要.
- 原生酶AtRpiB需要提高稳定性和效率,以生产D-.
研究的目的:
- 研究AtRpiB的催化特性,稳定性和基质结合亲和力.
- 为了设计AtRpiB,从D-psicose中增强D-allose的生产.
- 为了确定提高酶性能的关键突变.
主要方法:
- 用局部导向的突变发生法来创建AtRpiB.的单个和双重突变.
- 在不同温度下评估了酶活性,稳定性和转化效率.
- 进行了酶特征,结构分析和分子动力学模拟.
主要成果:
- 九个单个突变体表现出高的D-酸转化率.
- 特定的双重突变 (R109W/R132Q,S39I/R109F,S39V/R109F) 在高温 (40-80°C) 时显著增加了酶活性.
- 在40°C时,S39V/R109F突变物从100μg/L D-psicose中实现了38.21μg/L D-allose的创纪录的转化.
结论:
- 在AtRpiB中发生的突变可以显著提高D-素的生产效率和酶的稳定性.
- 特定循环 (3,9,10) 中的形状变化对于改善基质/产品相互作用和催化活性至关重要.
- 工程AtRpiB对可扩展的D-粉制造具有前景.
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