ビスアミノ酸ドナー-ブリッジ-受容体オリゴーマーを通じた水媒介による電子移転の実験的証拠
Subhasis Chakrabarti1, Matthew F L Parker, Christopher W Morgan
1University of Pittsburgh, Department of Chemistry, Pittsburgh, Pennsylvania 15260, USA.
Journal of the American Chemical Society
|January 29, 2009
まとめ
フォト誘発電子伝達は,水中のD-SSS-A分子では,水分子相互作用を促進する裂け目があるため,より速い. この電子トンネリング経路は,D-SRR-AまたはDMSOの溶媒条件と比較して転送速度を高めます.
科学分野:
- 物理化学 物理化学
- フォトケミストリー フォトケミストリー
- 分子生物物理学 分子生物物理学
背景:
- 光誘導による単分子電子移転は,化学と生物学における基本的なプロセスである.
- 溶媒の効果は,電子伝送のダイナミクスに大きな影響を与えます.
- 特定の空洞の存在などの分子構造は,溶液と溶媒の相互作用を媒介することができます.
研究 の 目的:
- 水とDMSOにおけるD-SSS-AとD-SRR-A溶液の光誘導単分子電子伝送速度の定数を比較する.
- D-SSS-Aにおける分子裂け目が電子伝送効率に与える影響を調査する.
- 特定の溶媒環境における強化された電子伝送のメカニズムを解明する.
主な方法:
- 電子伝送速度の定数を測定するための時間解像度スペクトロスコピー技術.
- D-SSS-AとD-SRR-Aを異なる溶媒 (水とDMSO) で比較した分析.
- 電子トンネリング経路を理解するための計算モデリング.
主要な成果:
- 水中のD-SSS-Aの速度常数は,D-SRR-Aの速度常数よりも大幅に高かった.
- 両方の溶液は,水と比較して,DMSOで大幅に高い速度常数を示した.
- 水分子を収容できるD-SSS-Aの亀裂の存在は,強化された電子伝送と関連していました.
- 水分子を含む電子トンネリング経路が,速度の上昇の原因として特定されました.
結論:
- 分子構造,特に裂け目が,特定の溶媒相互作用を促進することによって,光誘導電子伝送率を高めることができます.
- 水分子は,トンネリング経路を通って電子の転送を媒介する上で重要な役割を果たします.
- 溶媒の極性および分子構造は,電子伝送効率を左右する重要な要因である.
さらに関連する動画
11:04Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides
Published on: September 7, 2019
09:00Electrochemical Detection of Deuterium Kinetic Isotope Effect on Extracellular Electron Transport in Shewanella oneidensis MR-1
Published on: April 16, 2018
関連する概念動画
02:51Metal-Ligand Bonds
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
02:34Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
The rate of acid-catalyzed hydration of alkenes depends on the alkene's structure, as the presence of alkyl substituents at the double bond can significantly influence the rate.
01:16Titration in Nonaqueous Solvents
Most acid-base titrations are performed in an aqueous medium. In aqueous titrations, water competes with weaker acids or bases for proton donation or acceptance, leading to ambiguous endpoints in the titration curve. Water also affects the partial ionization of weak acids or bases. For example, water accepts a proton from acetic acid to form hydronium and acetate ions. The hydronium ion formed is a stronger acid than acetic acid, and the acetate ion is a stronger base than water. As a result,...
01:20Aldehydes and Ketones with Water: Hydrate Formation
An oxygen-based nucleophile, like water, can undergo addition reactions with aldehydes and ketones. The reaction leads to the formation of hydrates, also referred to as 1,1-diols or geminal diols.
The formation of hydrates is a reversible reaction. Hydrate formation is influenced by steric and electronic factors accompanying the alkyl substituents on the carbonyl group: The rate of hydrate formation increases with a decrease in the number of alkyl groups attached to the carbonyl carbon. Hence,...
The formation of hydrates is a reversible reaction. Hydrate formation is influenced by steric and electronic factors accompanying the alkyl substituents on the carbonyl group: The rate of hydrate formation increases with a decrease in the number of alkyl groups attached to the carbonyl carbon. Hence,...
02:35Noncovalent Attractions in Biomolecules
Noncovalent attractions are associations within and between molecules that influence the shape and structural stability of complexes. These interactions differ from covalent bonding in that they do not involve sharing of electrons.
Four types of noncovalent interactions are hydrogen bonds, van der Waals forces, ionic bonds, and hydrophobic interactions.
Hydrogen bonding results from the electrostatic attraction of a hydrogen atom covalently bonded to a strong-electronegative atom like oxygen,...
Four types of noncovalent interactions are hydrogen bonds, van der Waals forces, ionic bonds, and hydrophobic interactions.
Hydrogen bonding results from the electrostatic attraction of a hydrogen atom covalently bonded to a strong-electronegative atom like oxygen,...
01:22EDTA: Chemistry and Properties
Polydentate ligands are most widely used in complexometric titrations because they form more stable complexes with the metal ions than mono- or bidentate ligands due to the chelate effect. Examples of polydentate ligands are ethylenediaminetetraacetic acid (EDTA), crown ethers, and cryptands. The most important feature of optimal polydentate ligands is the ability to form 1:1 complexes in a single-step process. Amino carboxylic acid derivatives are frequently used as complexing agents. EDTA is...