电荷变化的结构和功能影响在氏丁酶ABC I中的作用
Amir Haghnazari1, Akram Shirdel1, Khosrow Khalifeh2
1Department of Biology, Faculty of Sciences, University of Zanjan, Zanjan, Iran.
International journal of biological macromolecules
|April 15, 2025
概括
通过引入负电荷 (A360E) 来修改Chondroitinase ABC I酶,提高了其稳定性和催化效率,为脊髓损伤 (SCI) 提供了潜在的再生疗法.
科学领域:
- 生物化学 生化学
- 蛋白质工程是指蛋白质工程.
- 神经科学是一个神经科学.
背景情况:
- 来自Proteus vulgaris的chondroitinase ABC I是脊髓损伤 (SCI) 后轴突再生的一个关键酶.
- 酶的原生小负电荷影响其功能.
- 表面电荷修饰是一种改善酶特性的潜在策略.
研究的目的:
- 为了研究表面电荷修饰对ondroitinase ABC I 稳定性和活性的影响.
- 为了设计一种具有增强性质的突变体,用于SCI的潜在治疗应用.
主要方法:
- 用局部导向的突变生成来用谷氨酸 (A360E) 或氨酸 (A360T) 取代360位的氨酸.
- 使用了结构建模 (MODELLER),光光谱学,循环二极化和热稳定性分析.
- 评估了催化效率,以评估酶的性能.
主要成果:
- 突变没有显著改变整体蛋白质结构,但诱导了更紧的构造.
- 与野生型和A360T相比,A360E突变体表现出增加的螺旋稳定性和更高的热稳定性.
- A360E表现出增强的催化效率,表明性能有所改善.
结论:
- 用负电荷 (A360E) 替换表面疏水性残留物可以提高酶的稳定性和可溶性.
- 增加蛋白质稳定性可能是由于有利的水相互作用和减少聚合.
- A360E突变体显示出在脊髓损伤 (SCI) 治疗中改善治疗疗效的潜力.
相关概念视频
01:18Indirect-Acting Cholinergic Agonists: Mechanism of Action
1.5K
Indirect-acting cholinergic agonists work by interacting with an enzyme called acetylcholinesterase (AChE) in the synaptic cleft. They can be reversible or irreversible inhibitors and have different effects on the enzyme.
Reversible inhibitors like edrophonium bind to a specific part of the enzyme called the anionic catalytic site. They form noncovalent bonds, which means they are not strongly attached to the enzyme. This creates a temporary and less stable enzyme–inhibitor complex,...
Reversible inhibitors like edrophonium bind to a specific part of the enzyme called the anionic catalytic site. They form noncovalent bonds, which means they are not strongly attached to the enzyme. This creates a temporary and less stable enzyme–inhibitor complex,...
1.5K
01:22Cholinesterases: Distribution and Function
376
Cholinesterases are a group of serine hydrolase enzymes that play a crucial role in the breakdown of choline esters. The two primary types of cholinesterases are acetylcholinesterases (AChEs) and butyrylcholinesterase (BuChEs), which differ in their distribution, function, and substrate specificity. AChEs, also known as true cholinesterases, specifically hydrolyze acetylcholine, while BuChEs, often referred to as pseudocholinesterases, can hydrolyze various choline esters, including...
376
01:31Substituent Effects on Acidity of Carboxylic Acids
6.5K
The acidity of carboxylic acids is influenced by the nature of the substituents bounded to the functional group. The acid strength is determined by the stability of the carboxylate anion—the conjugate base formed by dissociating the corresponding carboxylic acid.
6.5K
01:29Indirect-Acting Cholinergic Agonists: Chemistry and Structure-Activity Relationship
479
Indirect-acting cholinergic agonists are agents that interact with the acetylcholinesterase enzyme in the synaptic cleft, preventing the breakdown of acetylcholine into choline and acetate. Consequently, the concentration of acetylcholine in the synaptic cleft increases. These agonists can be classified into reversible and irreversible inhibitors based on their duration of action.
Reversible inhibitors display short to medium durations of action. Short-acting agents include simple alcohols with...
Reversible inhibitors display short to medium durations of action. Short-acting agents include simple alcohols with...
479
02:34Enzymes
80.2K
Inside living organisms, enzymes act as catalysts for many biochemical reactions involved in cellular metabolism. The role of enzymes is to reduce the activation energies of biochemical reactions by forming complexes with its substrates. The lowering of activation energies favor an increase in the rates of biochemical reactions.
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...
80.2K
00:49Ligand Binding and Linkage
4.7K
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...
4.7K