ライゾーイム分散におけるアニオンの非対称的な分割
Pierandrea Lo Nostro1, Niccolò Peruzzi, Mirko Severi
1Department of Chemistry and CSGI, University of Florence, 50019 Sesto Fiorentino, Florence, Italy. pln@csgi.unifi.it
Journal of the American Chemical Society
|April 17, 2010
まとめ
タンパク質分散は,硫酸ドデシルナトリウム相が分離し,2つの液体相を形成します. エレクトロライトは相分離に影響し,タンパク質分散は化学スポンジのように作用し,活発なポンプなしでタンパク質を濃縮します.
科学分野:
- 物理化学 物理化学
- バイオ物理化学 バイオ物理化学
- コロイド科学 コロイド科学
背景:
- タンパク質と表面活性物質の水中分散は,複雑な相行動を示すことができます.
- 段階分離の理解は,タンパク質の配製と加工に不可欠です.
- ホフマイスターシリーズは,タンパク質の溶解性および相互作用に対するイオン特異的な影響を記述しています.
研究 の 目的:
- 溶解酵素とドデシル硫酸ナトリウム (SDS) の相分離を水性分散液で調査する.
- 電解質が雲の点温度 (T ((c)) と相行動に及ぼす影響を決定する.
- 併存する液体相間のアニオンの分割と自己濃縮の可能性を探求する.
主な方法:
- ライゾジームとSDSの水性分散剤の準備.
- 異なる電解質条件下での雲点温度測定 (T(c)) です.
- 分離された液体相間のアニオン分割の分析.
- 段階分離現象の熱力学分析.
主要な成果:
- ライソジーム-SDS分散相は,雲点の下の2つの液体相に分離されます.
- 電解質は,逆のホフマイスター数列をたどって,T (c) を著しく変化させる.
- アニオンは,特定のアニオンに依存する2つの相の間の非対称的な分割を示します.
- 濃縮されたタンパク質相は化学スポンジとして作用し,活発なポンプなしで濃度差を可能にします.
結論:
- タンパク質-表面活性剤系における電解質誘発の相分離は,特定のイオン効果 (ホフマイスターシリーズ) によって制御される.
- 非対称なアニオン分割は,異なる液相の形成を促します.
- タンパク質分散はタンパク質を自発的に濃縮し,高濃度のタンパク質を達成するための受動的方法を提供します.
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