関連する実験動画
Updated: Jul 14, 2026
10:37
Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
陽子化されたポリペプチドから形成されるイオン/分子反応は,イオン/イオン電子のガス相移転を経由してカチオンラジカルから形成される
Yu Xia1, Paul A Chrisman, Sharon J Pitteri
1Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, USA.
Journal of the American Chemical Society
|September 7, 2006
まとめ
複数のプロトンを持つポリペプチドカチオンラジカルが酸素と反応し,活性化時に分裂するアダクトを形成します. この酸素反応は,タンパク質分析の改善のためにペプチド断片イオンを区別するのに役立ちます.
科学分野:
- アナリティカル・ケミストリー (Analytical Chemistry) とは
- バイオケミストリー バイオケミストリー
- 物理化学 物理化学
背景:
- 複数のプロトンを持つポリペプチドは,ガス相電子移転によってカチオンラジカルを形成する.
- 電子移転解離 (ETD) は,ペプチドとタンパク質の主要な構造の特徴づけに不可欠です.
- カチオンラジカルは,ETDの反応性中間物質である.
研究 の 目的:
- ポリペプチドカチオンラジカルと分子酸素の反応を研究する.
- ペプチド断片イオンを区別するためのこれらの反応の有用性を調査します.
- イオン/ラジカル反応がラジカル部位の位置を検知できるかどうかを判断する.
主な方法:
- ガス相電子移転により,プロトンを倍増したポリペプチドが形成される.
- 電子ダイナミックイオントラップにおけるカチオンラジカルと分子酸素の反応.
- 酸素誘導体の衝突による活性化.
- 分解産物の分析. 分解産物の分析. 分解産物の分析. 分解産物の分析. 分解産物の分析. 分解産物の分析. 分解産物の分析. 分解産物の分析.
主要な成果:
- カチオンラジカルは,室温で分子酸素 (O(2) を容易に結合する.
- 酸素は衝突活性化時に断片を添加し,O2をなくし,HO2をなくし,またはHO2をなくします.
- 断片イオン (z-イオン) はO2と反応し,c-イオンと区別する.
- 無傷の電子移転産物もまた, oxygen adducts を形成し,類似の解離行動を示す.
結論:
- 酸素によるイオン/ラジカル反応は,c型ペプチド断片イオンとz型ペプチド断片イオンを区別することができる.
- 酸素の結合と,その後の解離は,電子移転製品における基幹部位の位置を検知することができます.
- この反応性は,質量スペクトロメトリーを用いたタンパク質の識別と特徴づけのための新しいアプローチを提供します.
関連する概念動画
01:19Chemical Reactions
A chemical reaction is a process by which the bonds in the atoms of substances are rearranged to generate new substances. Matter cannot be created or destroyed in a chemical reaction—the same type and number of atoms that make up the reactants are still present in the products. Merely, the rearrangement of chemical bonds produces new compounds.
Chemical Reactions Rearrange Atoms into New Substances
A chemical reaction takes starting materials—the reactants—and changes them into different...
Chemical Reactions Rearrange Atoms into New Substances
A chemical reaction takes starting materials—the reactants—and changes them into different...
03:06Reaction Mechanisms
Chemical reactions often occur in a stepwise fashion, involving two or more distinct reactions taking place in a sequence. A balanced equation indicates the reacting species and the product species, but it reveals no details about how the reaction occurs at the molecular level. The reaction mechanism (or reaction path) provides details regarding the precise, step-by-step process by which a reaction occurs.
For instance, the decomposition of ozone appears to follow a mechanism with two steps:
For instance, the decomposition of ozone appears to follow a mechanism with two steps:
02:26Chemical Reactions
A balanced chemical equation provides the information of chemical formulas of the reactants and products involved in the chemical change. A reaction’s stoichiometry helps predict how much of the reactant is needed to produce the desired amount of product, or in some cases, how much product will be formed from a specific amount of the reactant.
The relative amounts of reactants and products represented in a balanced chemical equation are often referred to as stoichiometric amounts. However, in...
The relative amounts of reactants and products represented in a balanced chemical equation are often referred to as stoichiometric amounts. However, in...
02:13Energy Diagrams, Transition States, and Intermediates
Free-energy diagrams, or reaction coordinate diagrams, are graphs showing the energy changes that occur during a chemical reaction. The reaction coordinate represented on the horizontal axis shows how far the reaction has progressed structurally. Positions along the x-axis close to the reactants have structures resembling the reactants, while positions close to the products resemble the products. Peaks on the energy diagram represent stable structures with measurable lifetimes, while other...
01:08Types of Chemical Reactions: Exchange and Reversible
An exchange reaction is a chemical reaction in which both synthesis and decomposition occur, chemical bonds are both formed and broken, and chemical energy is absorbed, stored, and released.
A special kind of exchange reaction is the oxidation-reduction reaction, or the redox reaction. These reactions involve the transfer of electrons from one compound to another. The electrons in these reactions commonly come from hydrogen atoms, which consist of an electron and a proton. A molecule gives up a...
A special kind of exchange reaction is the oxidation-reduction reaction, or the redox reaction. These reactions involve the transfer of electrons from one compound to another. The electrons in these reactions commonly come from hydrogen atoms, which consist of an electron and a proton. A molecule gives up a...
01:17Ion Exchange
Ion exchange chromatography separates charged molecules from a solution by reversibly exchanging them with mobile, or 'active', ions associated with the oppositely charged stationary phase. This method can be used to separate ions, soften and deionize water, and purify solutions. The polymers comprising the ion-exchange column are high-molecular-weight and chemically stable polymers, crosslinked to be porous and essentially insoluble. They are also functionalized with either acidic or basic...