不逆のペプチド標的化のためのサイドチェーン間の自発的な分子間アミド結合形成
1Department of Biochemistry, Oxford University, South Parks Road, Oxford, OX1 3QU, UK.
Journal of the American Chemical Society
|March 19, 2010
まとめ
研究者は,アミド結合形成を通じてタンパク質に不可逆的に結合する新しい16アミノ酸ペプチドタグを開発しました. この安定したペプチドタグは,タンパク質分析,バイオアセンブリ,およびセルラーイメージングアプリケーションの新たな可能性を提供します.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- 合成生物学 合成生物学とは
背景:
- ペプチドは生物学的分析に不可欠ですが,不安定な相互作用に苦しんでいます.
- 制限された表面積と柔軟性は,ペプチド-タンパク質結合の安定性を妨げます.
- 既存のペプチドタグは小さいので,タンパク質機能の混乱を最小限に抑えることができます.
研究 の 目的:
- タンパク質パートナーと安定した,不可逆的なアミド結合を形成するペプチドタグを設計する.
- この目的のために,ピリンサブユニットから分子内アミド結合形成を活用する.
- 堅牢なタンパク質のラベル付けと修正を可能にするために.
主な方法:
- Streptococcus pyogenes pilin.から派生した16アミノ酸ペプチドを設計した.
- リジンとアスパラジン側鎖の間の自発的なアミド結合形成を利用した.
- テストされた反応効率,pH/温度依存度,およびバッファの互換性.
- in vitroおよびin vivo (E. coli,哺乳類の細胞) で評価された性能.
主要な成果:
- ペプチドとタンパク質のパートナー間のアミド結合形成における98%の変換を達成しました.
- 反応は,pH5-8を超えて,様々なバッファで,そして酸化還元状態から独立して効率的に発生しました.
- 4°Cと37°Cで同様の反応速度を観測した.
- E. coliで効率的に溶解し,哺乳類の細胞に特定の表面ラベルを付けることが実証されています.
結論:
- アミド結合形成による不可逆的なタンパク質ターゲティングを可能にするペプチドタグを開発.
- タグは安定し,効率的で,多様な生物学的条件とシステムで機能します.
- 潜在的な応用には,バイオアセンブリ,細胞イメージング,および力によるタンパク質複合体の安定化が含まれます.
関連する概念動画
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Amides are synthesized by treating carboxylic acids with amines in the presence of dehydrating agents like dicyclohexylcarbodiimide (DCC).
The DCC-promoted synthesis of amides begins with the protonation of DCC by carboxylic acid. The protonation makes it a better acceptor. Next, the addition of carboxylate to the protonated carbodiimide gives a reactive acylating agent.
Subsequently, the amine acts as a nucleophile that attacks the acylating agent to form a tetrahedral intermediate. In the...
The DCC-promoted synthesis of amides begins with the protonation of DCC by carboxylic acid. The protonation makes it a better acceptor. Next, the addition of carboxylate to the protonated carbodiimide gives a reactive acylating agent.
Subsequently, the amine acts as a nucleophile that attacks the acylating agent to form a tetrahedral intermediate. In the...
Amides to Carboxylic Acids: Hydrolysis
Amides can undergo either acid-catalyzed hydrolysis or base-promoted hydrolysis through a typical nucleophilic acyl substitution. Each hydrolysis requires severe conditions.
Acid-catalyzed hydrolysis:
Hydrolysis of amides under acidic conditions yields carboxylic acids. Since the reaction occurs slowly, hydrolysis requires the conditions of heat.
The mechanism begins with the protonation of the carbonyl oxygen by the acid catalyst. The protonation makes the amide carbonyl carbon more...
Acid-catalyzed hydrolysis:
Hydrolysis of amides under acidic conditions yields carboxylic acids. Since the reaction occurs slowly, hydrolysis requires the conditions of heat.
The mechanism begins with the protonation of the carbonyl oxygen by the acid catalyst. The protonation makes the amide carbonyl carbon more...
Amines to Amides: Acylation of Amines
Various carboxylic acid derivatives (such as acid chlorides, esters, and anhydrides) can be used for the acylation of amines to yield amides. The reaction requires two equivalents of amines. The first amine molecule functions as a nucleophile and attacks the carbonyl carbon to produce a tetrahedral intermediate. This is followed by the loss of the leaving group and restoration of the C=O bond.
Next, the second equivalent of amine serves as a Brønsted base and deprotonates the quaternary amide...
Next, the second equivalent of amine serves as a Brønsted base and deprotonates the quaternary amide...
Protein Organization
Overview
Protein Organization
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The primary structure of a protein is its amino acid sequence.
The primary structure of a protein is its amino acid sequence.


