相关实验视频

Updated: Sep 14, 2025

Structural Biology and Analytical Chemistry Approaches for Characterizing C-Glycoside Metabolic Enzymes in Human Gut Microbiota

Structural Biology and Analytical Chemistry Approaches for Characterizing C-Glycoside Metabolic Enzymes in Human Gut Microbiota

Published on: May 23, 2025

对来自Saccharolobus solfataricus的谷氨酸脱酶独特的基质特异性的结构洞察

Itsuki Okabe¹, Masashi Hirano², Taketo Ohmori³

¹Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, 2393 Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0795, Japan.

Extremophiles : life under extreme conditions

|July 24, 2025

概括

这项研究过度表达了来自Saccharolobus solfataricus P2.2的L-谷氨酸脱酶 (GDH) 同类物. 该酶在中等温度下对L-norvaline表现出更高的活性,Met93调解了这种独特的基质特异性.

科学领域:

生物化学生物化学
结构生物学结构生物学
酶学是一种酶学.

背景情况:

L-谷氨酸脱酶 (GDH) 酶在氨基酸代谢中至关重要.
热酸性古生物拥有独特的酶,适应极端环境.
了解酶特异性是生物催化剂和蛋白质工程的关键.

研究的目的:

来自Saccharolobus solfataricus P2.2.的L-谷氨酸脱酶 (GDH) 同源 (SSO1457) 的特征.
阐明SSO1457基质特异性的结构基础,特别是对L-诺瓦林的特异性.
研究特定氨基酸残留在酶活性和特异性中的作用.

主要方法:

在大肠杆菌中SSO1457基因的过度表达.
在不同温度和基质度下进行酶活性测定.
确定与NAD+/2-oxovalerate和NAD+/2-oxoglutarate结合的SSO1457的晶体结构.
位点定向的突变发生以探测残留的功能.

主要成果:

在55-75°C之间,SSO1457对L-诺瓦林的特异活性高于L-谷氨酸.
在85°C时,酶活性转向有利于L-谷氨酸.
晶体结构显示了2-oxovalerate (疏水性) 和2-oxoglutarate (结合) 的明显的结合相互作用.
甲氨酸93 (Met93) 被确定为对L-诺瓦林的反应性和高特异性活性至关重要.

结论:

SSO1457具有独特的基质特异性,其特异性受温度的影响.
涉及Met93的疏水相互作用对于定L-诺瓦林并赋予高活性至关重要.
这项研究提供了对GDH基质识别和工程生物催化剂潜力的结构性见解.

关键词:

晶体结构晶体结构谷氨酸脱酶的作用是什么超热友性酶超热友性酶是一种超热友性酶.分子动力学模拟模型基质特异性基质特异性

更多相关视频

Direct Detection of the Acetate-forming Activity of the Enzyme Acetate Kinase

Direct Detection of the Acetate-forming Activity of the Enzyme Acetate Kinase

Published on: December 19, 2011

Monitoring Intraspecies Competition in a Bacterial Cell Population by Cocultivation of Fluorescently Labelled Strains

Monitoring Intraspecies Competition in a Bacterial Cell Population by Cocultivation of Fluorescently Labelled Strains

Published on: January 18, 2014

相关概念视频

Ligand Binding and Linkage

Ligand Binding and Linkage

Allosteric proteins have more than one ligand binding site; the binding of a ligand to any of these sites influences the binding of ligands to the other sites. When a protein is allosteric, its binding sites are called coupled or linked. In the case of enzymes, the site that binds to the substrate is known as the active site and the other site is known as the regulatory site. When a ligand binds to the regulatory site, this leads to conformational changes in the protein that can influence...

Allosteric Proteins-ATCase

Allosteric Proteins-ATCase

Binding sites linkages can regulate a protein's function. For example, enzyme activity is often regulated through a feedback mechanism where the end product of the biochemical process serves as an inhibitor.
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis...