循環性ヘキサペプチドのペプチド結合によるトリプトファン光の内分子滅
Paul D Adams1, Yu Chen, Kan Ma
1Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106-7078, USA.
Journal of the American Chemical Society
|August 1, 2002
まとめ
この研究は,トリプトファンの光が硬質ペプチドの中でどのように消されるかを明らかにしています. トリプトファンの側面鎖の異なる方向性 (ロタマー) は,電子伝送率のために光寿命に大きく影響します.
科学分野:
- バイオ物理化学 バイオ物理化学
- スペクトロスコーピーは,スペクトロスコーピーを用います.
- タンパク質の構造とダイナミクス
背景:
- トリプトファンの光は,その局所環境に対して敏感である.
- タンパク質機能の研究には,分子内冷却機構の理解が不可欠である.
研究 の 目的:
- 硬いサイクルヘキサペプチドにおけるトリプトファン光の分子内解消を調査する.
- ペプチド構造,特にトリプトファン側鎖ロタマーを光特性と相関させるため.
主な方法:
- 1Dと2D (1) H核磁気共振 (NMR) スペクトロスコーピーは,溶液構造を決定する.
- ペプチドの寿命を測定するための光スペクトロスコーピー.
- 電子伝送率を計算するためのマーカス理論.
主要な成果:
- 主要なペプチド骨格構造が特定されました.
- 3つの異なるトリプトファンの光寿命 (3.8,1.8,0.3ns) が観察され,3つのチーと相関していた.
- 主要な3.8nsの寿命は,支配的なchi (((1) = -60度ロータマーに対応しています.
結論:
- 光寿命は,トリプトファンのサイドチェーンロータマー集団によって直接影響を受けます.
- ペプチド結合への電子移転が,主な消火メカニズムである.
- 刺激状態の分子内プロトン伝達は,このシステムにおける重要な消火経路ではない.
関連する概念動画
Peptide Bonds
A peptide bond covalently attaches amino acids through a dehydration reaction. One amino acid's carboxyl group and another amino acid's amino group combine, releasing a water molecule. The resulting bond is the peptide bond. The products that such linkages form are peptides. As more amino acids join this growing chain, the resulting chain is a polypeptide. Each polypeptide has a free amino group at one end. This end has the N-terminal, or the amino-terminal, and the other end has a free...
Transcription Attenuation in Prokaryotes
Transcriptional attenuation occurs when RNA transcription is prematurely terminated due to the formation of a terminator mRNA hairpin structure. Bacteria use these hairpins to regulate the transcription process and control the synthesis of several amino acids including histidine, lysine, threonine, and phenylalanine. Transcription attenuation takes place in the non-coding regions of mRNA.
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
Aromatic Hydrocarbon Cations: Structural Overview
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group with both...
Removing one hydrogen from the intervening CH2 group with both...
Variables Affecting Phosphorescence and Fluorescence
Fluorescence and phosphorescence are essential phenomena in fields like analytical chemistry, biological imaging, and materials science, where they detect molecular properties and visualize cellular structures. Understanding the variables that influence these luminescent behaviors is crucial for maximizing accuracy and efficiency in their applications. These variables can broadly be grouped into chemical structure, solvent properties, and external conditions, each playing a distinct role in...
Repressible Operon: trp Operon
The trp operon in Escherichia coli exemplifies a repressible operon. It regulates the synthesis of tryptophan through repressor-mediated transcriptional control and attenuation. This dual regulatory mechanism ensures tryptophan biosynthesis occurs only when needed, conserving cellular resources.Structure of the trp OperonThe trp operon consists of five structural genes (trpE, trpD, trpC, trpB, and trpA) that encode enzymes for tryptophan biosynthesis. These genes are transcribed as a single...


