pHはペプチドβシートの自己組み立てとネマティックとイソトロピック相の間の可逆的な切り替えを誘発する
Amalia Aggeli1, Mark Bell, Lisa M Carrick
1Centre for Self-Organising Molecular Systems, University of Leeds, UK.
Journal of the American Chemical Society
|August 9, 2003
まとめ
研究者は,pHを調整することで,ゲルのような秩序ある構造に素早く自己組み立てられるペプチドを設計しました. このpH誘発制御は,合成ペプチドから高度な柔らかい材料を作成するための迅速かつ可逆的な方法を提供します.
科学分野:
- 超分子化学 超分子化学
- マテリアルサイエンス 材料科学
- バイオテクノロジー バイオテクノロジー
背景:
- ベータシート構造 (テープ,リボン,繊維,繊維) に合成ペプチドの階層的な自己組み立ては,柔らかい固体のような材料への有望な経路です.
- 溶融化ペプチド溶解などのペプチドの自己組み立てのための既存の方法は,時間がかかります (数時間から数日間).
研究 の 目的:
- pHを用いたペプチドの自己組立を制御するための迅速かつ可逆的な方法を開発する.
- pHの変化によって引き起こされる異なる状態 (例えば,イソトロプ液体からネマティックゲル) 間で移行できる合成ペプチドを設計する.
主な方法:
- 酸性 (Glu) または塩基性 (Orn) アミノ酸を11アミノ酸ペプチド配列に組み込む.
- ペプチドの自己組織化運動と物質状態 (ネマティックゲル,同位体流体) に及ぼすpHの影響を調査する.
- 組み込まれたアミノ酸残留物のデプロトネーションの振る舞いを特徴付けるために,酸塩定位を使用する.
主要な成果:
- オーダーされた線維構造にペプチドの自己組み立ては,迅速 (数秒) で,pHの変化によって可逆的に制御することができます.
- 設計されたペプチド (P(11) - 4およびP(11) - 5) は,同位体流体とネマティックゲル状態の間のpH依存の移行を示しています.
- 自己組み立てプロセスは,GluとOrn残基のプロトネーション状態に影響される静電相互作用によって制御されます.
結論:
- GluまたはOrnの残留物を組み込むことは,ペプチドの自己組み立てをpH媒介で正確に制御することを可能にします.
- このアプローチは,ペプチドベースの柔らかい材料を作成するための伝統的な方法に比べて,著しく速い代替手段を提供します.
- この発見は,調節可能な性質を持つ反応性ペプチド材料の開発のための設計原理を提供します.
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