核酸ヘリックス形成に対する尿素効果を決定する機能群相互作用の定量化
Emily J Guinn1, Jeffrey J Schwinefus, Hyo Keun Cha
1Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Journal of the American Chemical Society
|March 21, 2013
まとめ
尿素は,核酸やタンパク質を不安定化する. この研究では,尿素を定量化しています.
科学分野:
- バイオ物理化学 バイオ物理化学
- 分子生物学は分子生物学である.
- 化学熱力学 化学熱力学
背景:
- 尿素はタンパク質,核酸,およびそれらの複合体の構造を破壊することが知られている.
- 尿素と生物分子の相互作用を理解することは,形状の変化を調査するために重要である.
- 以前の研究では,タンパク質の機能群との尿素の相互作用を特徴づけた.
研究 の 目的:
- 尿素と核酸成分 (塩基,ヌクレオシド,ヌクレオチド) の間の相互作用を定量化するために.
- 核酸プロセスにおける構成変化の定量的な探査機として尿素を開発する.
- 特定の核酸の機能群と尿素の相互作用の可能性を決定する.
主な方法:
- オスモメトリーとヘクサノール-水配分アッセイを用いて,化学潜在的な誘導体 (μ23) を測定した.
- 尿素-核酸成分相互作用の μ23 値を解剖することによって得られた相互作用ポテンシャル.
- DNAデデカメアのダブルヘリックス形成のための尿素m値の決定.
主要な成果:
- 尿素は,水と比較して,核酸の機能群 (芳香環,カルボニル,リン酸,砂糖) と好ましい相互作用をします.
- ヘテロサイクルアロマティックリングやメチル群との相互作用は特に好ましい.
- DNAのダブルヘリックス形成のウレアm値 (0.72-0.85 kcal mol(-1) m(-1)) はGC含有量への依存性はほとんどなかった.
結論:
- 観察された尿素m値を説明するために,分離されたDNA鎖の広範な核塩基スタッキング (60-90%) が必要である.
- 結果は,さまざまな温度でDNAとRNAの12カメラーに一致し,文献データと一致しています.
- 尿素は,核酸プロセス中のアクセス可能な表面積 (ΔASA) の変化のための貴重な定量的なプローブとして機能します.
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