レドックス活性アミノ酸のサイト固有の組み込みがタンパク質に含まれる
Lital Alfonta1, Zhiwen Zhang, Sean Uryu
1Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
Journal of the American Chemical Society
|December 3, 2003
まとめ
研究者は,E. coliのTAGコードンを用いて,酸化還元活性アミノ酸3,4-ジヒドロキシ-l-フェニララニン (DHP) をタンパク質に組み込みました. このDHPは,タンパク質内で電気化学的に酸化され,新しい研究とリドックスタンパク質のエンジニアリングを可能にします.
科学分野:
- バイオケミストリーと分子生物学
- バイオエンジニアリング バイオエンジニアリング
- 電気化学 電気化学について
背景:
- タンパク質には,その機能に不可欠な酸化還元活性アミノ酸がしばしば含まれています.
- 非正規のアミノ酸のサイト固有の組み込みは,タンパク質工学を可能にします.
- 3,4-ジヒドロキシ-l-フェニララニン (DHP) は,二電子酸化を行うことができる酸化還元活性アミノ酸です.
研究 の 目的:
- レドックス活性アミノ酸DHPを選択的かつ効率的にタンパク質に組み込む.
- タンパク質内に組み込まれたDHPの電気化学的酸化性を実証する.
- 電子移転の研究と新しい酸化還元タンパク質の設計の可能性を探求する.
主な方法:
- DHPのサイト固有の組み込みのために,Escherichia coliのTAGコドンを利用しました.
- タンパク質構造内に組み込まれたDHPを酸化するために電気化学的方法を使用しました.
主要な成果:
- E. coli のタンパク質に DHP の選択的かつ効率的な組み込みが達成されました.
- DHPをタンパク質内のキノンの形に電気化学的に酸化することを成功裏に実証しました.
- サイト固有のリドックス活性アミノ酸の組み込みの可行性を検証しました.
結論:
- DHPのサイト固有の組み込みは,E. coliでは実現可能である.
- 組み込まれたDHPは,その酸化還元活性を維持し,電気化学的に制御することができます.
- この方法は,タンパク質の電子移転を研究し,新しい酸化還元機能を設計するための道を開きます.
関連する概念動画
01:13Protein Organization
Overview
01:26Protein Modifications in the RER
Modification of secretory and transmembrane proteins entering the rough ER begins in the ER lumen. These modifications aid in protein folding and stabilize the acquired tertiary structure. Protein modifications in the rough ER co-occur at different stages of protein folding.
Broadly, these modifications can be categorized into four main categories — glycosylation, formation of disulfide bonds, assembly of protein subunits, and specific proteolytic cleavages like removal of signal sequences.
Broadly, these modifications can be categorized into four main categories — glycosylation, formation of disulfide bonds, assembly of protein subunits, and specific proteolytic cleavages like removal of signal sequences.
01:19Oxidation and Reduction of Organic Molecules
Energy production within a cell involves many coordinated chemical pathways. Most of these pathways are combinations of oxidation and reduction reactions, which occur at the same time. An oxidation reaction strips an electron from an atom in a compound, and the addition of this electron to another compound is a reduction reaction. Because oxidation and reduction usually occur together, these pairs of reactions are called redox reactions.
The removal of an electron from a molecule, results in a...
The removal of an electron from a molecule, results in a...
01:28What are Proteins?
Proteins are polymers of amino acids linked together by peptide bonds. Proteins and polypeptides are interchangeably used to refer to long chains of amino acids. However, polypeptides have a molecular weight of fewer than 10,000 daltons, while proteins have greater molecular weight. Polypeptides with less than 20 amino acids are called oligopeptides or simply peptides. Interactions among the constituent amino acid side chains of proteins help them fold into a stable 3-dimensional structure...
01:24Protein Organization
Proteins are polymers of amino acid residues. They are versatile and responsible for different cellular functions, including DNA replication, molecular transport, catalysis, and structural support. Proteins have a hierarchical structure comprising at least three levels of organization: primary, secondary, and tertiary structure. Some large proteins have a quaternary structure where individual protein subunits are linked together.
The primary structure of a protein is its amino acid sequence.
The primary structure of a protein is its amino acid sequence.
01:28Protein Denaturation
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...