タンパク質表面でのアミノ酸置換によって緩和される逆水性効果
1Department of Biology, Massachusetts Institute of Technology, Cambridge 02139.
Nature
|March 22, 1990
まとめ
タンパク質の表面上のアミノ酸の置換は,安定性にほとんど影響しません. しかし,LambdaCroタンパク質の26位での変異は安定性を著しく高め,サイドチェーンの水害性低下と相関しています.
科学分野:
- タンパク質の生化学
- 分子生物学は分子生物学である.
- 構造生物学 構造生物学とは
背景:
- タンパク質表面におけるアミノ酸の置換は,通常,タンパク質の安定性に最小限の影響を及ぼします.
- ラムダクロタンパク質は,タンパク質の安定性を研究するためのモデルシステムです.
研究 の 目的:
- タンパク質の安定性に対するラムダ・クロの位置26のアミノ酸置換の影響を調査する.
- この表面曝露の位置におけるサイドチェーンの水性およびタンパク質の安定性との関係を調査する.
主な方法:
- サイト・ディレクテッド・ミュータゲネシスにより,Lambda Cro.の位置26に様々なアミノ酸の置換を導入する.
- 溶解温度とタンパク質の安定性の変化を測定するための差分スキャニングカロメトリー.
- 残留物の溶媒アクセシビリティを評価するために,Cro結晶構造の分析 26.
主要な成果:
- Lambda CroにおけるA Tyr 26 to Cys変異により,融解温度が11°C,安定性は2.2 kcal mol-1.0で上昇した.
- 位置26の複数のアミノ酸の置換により,タンパク質の安定性が向上した.
- タンパク質の安定性の向上は,位置26のサイドチェーン水嫌性の低下と相関する.
結論:
- 表面アミノ酸の置換は,タンパク質の安定性を大幅に変化させることができます.
- ラムダ・クロのハイパー露出位置26の水害性側鎖は,逆の水害性効果によって不安定化しているようです.
- 特定の表面残留物に対する水嫌性を調節することは,タンパク質の工学と安定化のための戦略を提供します.
さらに関連する動画
10:31Residue-Specific Exchange of Proline by Proline Analogs in Fluorescent Proteins: How "Molecular Surgery" of the Backbone Affects Folding and Stability
Published on: February 3, 2022
06:50Computational Prediction of Amino Acid Preferences of Potentially Multispecific Peptide-Binding Domains Involved in Protein-Protein Interactions
Published on: January 26, 2024
関連する概念動画
Protein Folding
Overview
Amino acids
Amino acids are the monomers that comprise proteins. Each amino acid has the same fundamental structure, which consists of a central carbon atom, or the alpha (α) carbon, bonded to an amino group (NH2), a carboxyl group (COOH), and to a hydrogen atom. Every amino acid also has another atom or group of atoms bonded to the central atom known as the R group. There are 20 common amino acids present in proteins, each with a different R group. Variation in the amino acid sequence is responsible for...
Ligand Binding Sites
Proteins are dynamic macromolecules that carry out a wide variety of essential processes; however, the activities of most proteins depend on their interactions with other molecules or ions, known as ligands.
Protein-ligand interactions are quite specific; even though numerous potential ligands surround a cellular protein at any given time, only a particular ligand can bind to that protein. Moreover, a ligand binds only to a dedicated area on the surface of the protein, known as the...
Protein-ligand interactions are quite specific; even though numerous potential ligands surround a cellular protein at any given time, only a particular ligand can bind to that protein. Moreover, a ligand binds only to a dedicated area on the surface of the protein, known as the...
Conserved Binding Sites
Many proteins’ biological role depends on their interactions with their ligands, small molecules that bind to specific locations on the protein known as ligand-binding sites. Ligand-binding sites are often conserved among homologous proteins as these sites are critical for protein function.
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally analyses the...
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally analyses the...
Aquaporins
Aquaporins or AQPs are a family of integral membrane proteins whose primary function is to transport water, while some called aquaglyceroporins also transport glycerol. In addition, aquaporins have also been suspected to be involved in transporting volatile substances, such as carbon dioxide and ammonia, across membranes. Such AQPs that act as gas channels are often highly expressed in cells involved in the gaseous exchange, such as red blood cells, epithelial cells, and pulmonary capillaries.
Protein Folding
Proteins are chains of amino acids linked together by peptide bonds. Upon synthesis, a protein folds into a three-dimensional conformation, critical to its biological function. Interactions between its constituent amino acids guide protein folding, and hence the protein structure is primarily dependent on its amino acid sequence.
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
