• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>International Journal of Biological Macromolecules: Structure, Function and Interactions >Elucidating the regulation of glucose tolerance in a beta-glucosidase from Halothermothrix orenii by active site pocket engineering and computational analysis
【24h】

Elucidating the regulation of glucose tolerance in a beta-glucosidase from Halothermothrix orenii by active site pocket engineering and computational analysis

机译：通过主动点袖珍工程和计算分析，从Halothermothrix orenii阐明β-葡糖苷酶中葡萄糖耐受的调节

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

beta-Glucosidase catalyzes the hydrolysis of beta-1,4 linkage between two glucose molecules in cello-oligosaccharides and is prone to inhibition by the reaction product glucose. Relieving the glucose inhibition of beta-glucosidase is a significant challenge. Towards the goal of understanding how glucose interacts with beta-glucosidase, we expressed in Escherichia colt, the Hore_15280 gene encoding a beta-glucosidase in Halotheimothrix orenii. Our results show that the enzyme is glucose tolerant, and its activity on p-nitrophenyl D-glucopyranoside stimulated in the presence of up to 0.5 M glucose. NMR analyses show the unexpected interactions between glucose and the beta-glucosidase at lower concentrations of glucose that, however, does not lead to enzyme inhibition. We identified non-conserved residues at the aglycone-binding and the gatekeeper site and show that increased hydrophobicity at the pocket entrance and a reduction in steric hindrances are critical towards enhanced substrate accessibility and significant improvement in activity. Analysis of structures and in combination with molecular dynamics simulations show that glucose increases the accessibility of the substrate by enhancing the structural flexibility of the active site pocket and may explain the stimulation in specific activity up to 0.5 M glucose. Such novel regulation of beta-glucosidase activity by its reaction product may offer novel ways of engineering glucose tolerance. (C) 2020 Elsevier B.V. All rights reserved.
机译：β-葡萄糖苷酶催化β-1,4连杆的水解β-1,4连杆在细胞 - 寡糖中的两个葡萄糖分子之间，并且易于通过反应产物葡萄糖抑制。缓解β-葡糖苷酶的葡萄糖抑制是一个重大挑战。朝与β-葡萄糖苷酶了解如何葡萄糖交互的目标，我们在大肠埃希菌中表达的基因Hore_15280编码Halotheimothrix orenii一种β-葡萄糖苷酶。我们的研究结果表明，酶是葡萄糖耐受性，其在高达0.5M葡萄糖存在下刺激的对硝基苯基D-吡喃葡萄糖苷的活性。 NMR分析显示葡萄糖和β-葡糖苷酶之间的意外相互作用，但较低浓度的葡萄糖，然而，不会导致酶抑制。我们鉴定了糖苷酮结合的非保守残留物，并且显示出在袋入口处增加的疏水性和空间障碍的降低对增强的基底可接近性和显着的活性改善至关重要。结构分析和与分子动力学模拟的组合表明，葡萄糖通过增强活性位点口袋的结构柔韧性来增加基材的可触及性，并且可以将特定活性的刺激解释至0.5μm的葡萄糖。其反应产物的这种新型调节β-葡糖苷酶活性可以提供新的工程葡萄糖耐量的方式。 （c）2020 Elsevier B.v.保留所有权利。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号