/交换对溶液和气相中的蛋白质稳定性的影响
Yousef Haidar1, Lars Konermann1
1Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada.
Journal of the American Society for Mass Spectrometry
|June 14, 2023
概括
在重水 (D2O) 中的化蛋白显示出更高的稳定性,具有更高的化温度. 这种稳定是由于溶剂的影响,而不是蛋白质与蛋白质相互作用的变化,尽管确切的机制需要进一步研究.
科学领域:
- 生物物理学的生物物理.
- 结构生物学 结构生物学
- 质谱测量质量谱测量
背景情况:
- 基于质谱 (MS) 的技术,包括/交换 (HDX) -MS,对于研究蛋白质结构和动态至关重要.
- HDX-MS通常被认为是无干扰的,但一些证据表明D2O可能会稳定蛋白质,这一说法仍在争论中.
- 之前的假设认为D2O中的蛋白质稳定是由于较低的零点振动能量而加强的键.
研究的目的:
- 通过实验证实和研究D2O与H2O相比观察到的蛋白质稳定性的起源.
- 要区分溶剂效应和蛋白内相互作用的变化,从而促进蛋白质稳定.
- 评估水-水 (W···W),水-蛋白 (W···P) 和蛋白-蛋白 (P···P) 相互作用在D2O诱导稳定中的作用.
主要方法:
- 在H2O和D2O中对蛋白质进行了热展开测试,以测量化温度.
- 碰撞诱导展开 (CIU) 实验是在通过本地电喷气电离生成的气态蛋白质 (未标记和化) 上进行的.
- 分析的重点是比较展开的配置文件,以探讨化对蛋白内接触的影响.
主要成果:
- 与H2O中的蛋白质相比,D2O中的蛋白质表现出明显更高的化温度 (2-4K),证实了增强的稳定性.
- 气相中的脱和未标记蛋白质的碰撞诱导展开 (CIU) 配置文件几乎相同.
- 无法区分的CIU配置文件表明,蛋白质与蛋白质 (P···P) 接触不受化影响.
结论:
- 在D2O中蛋白质稳定主要是由溶剂效应驱动的,而不是由蛋白质内键或蛋白质与蛋白质相互作用的变化驱动的.
- 观察到的稳定可能源于D2O中加强的水-水 (W··W) 键或减弱的水-蛋白 (W···P) 键.
- 需要进一步的研究来确定W··W和W··P相互作用对D2O中蛋白质稳定的确切贡献.
更多相关视频
09:18Time-resolved ElectroSpray Ionization Hydrogen-deuterium Exchange Mass Spectrometry for Studying Protein Structure and Dynamics
Published on: April 17, 2017
9.9K
11:32A Hydrogen-Deuterium Exchange Mass Spectrometry HDX-MS Platform for Investigating Peptide Biosynthetic Enzymes
Published on: May 4, 2020
8.1K
相关概念视频
¹H NMR of Labile Protons: Deuterium (²H) Substitution
929
This lesson illustrates the role of deuterium substitution in simplifying the NMR spectrum of compounds comprising labile protons. One method employed is the use of deuterium. Amongst the three isotopes of hydrogen, deuterium (2H) has a nucleus composed of one proton and one neutron. When the D2O solvent is added to a pure dry ethanol solution, its labile proton is substituted with deuterium.
929
Hydrogen Bonds
8.7K
A hydrogen bond is formed when a weakly positive hydrogen atom already bonded to one electronegative atom (for example, the oxygen in the water molecule) is attracted to another electronegative atom from another polar molecule, such as water (H2O), hydrogen fluoride (HF), or ammonia (NH3). The huge electronegativity difference between the H atom (2.1) and the atom to which it is bonded (4.0 for an F atom, 3.5 for an O atom, or 3.0 for an N atom), combined with the very small size of an H atom...
8.7K
Protein Denaturation
4.4K
The function of proteins depends on their native three-dimensional structure, which is dictated by the amino acid sequence of the specific protein. Folding of the polypeptide chain takes place under specific conditions that energetically favor the folded conformation. In contrast, protein denaturation occurs spontaneously under unfavorable conditions that disrupt the integrity of the folded conformation. Thus, the chemical and physical environment of a protein, such as significant changes in pH...
4.4K
Reduction of Alkenes: Catalytic Hydrogenation
12.2K
Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
12.2K
Relative Stabilities of Alkenes
14.0K
The relative stability of alkenes can be determined by comparing their heats of hydrogenation. The lower heat of hydrogenation indicates the more stable alkene. The three main factors determining the relative stability of alkenes are i) the number of substituents attached to the double-bond carbon atoms, ii) hyperconjugation, and iii) the stereochemistry of the double bond.
14.0K
Stability of Conjugated Dienes
3.4K
Introduction
A comparison of the enthalpies of hydrogenation of dienes reveals that conjugated dienes release less heat on hydrogenation, rendering them more stable than their nonconjugated analogs.
A comparison of the enthalpies of hydrogenation of dienes reveals that conjugated dienes release less heat on hydrogenation, rendering them more stable than their nonconjugated analogs.
3.4K
