分子機械化学:低力スイッチは,ヒトのタイプIコラーゲンモノメールの酵素分裂を遅らせます
Robert J Camp1, Melody Liles, John Beale
1Department of Mechanical and Industrial Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massuachusetts 02115, United States.
Journal of the American Chemical Society
|February 26, 2011
まとめ
機械的な力は,コラーゲンを分解に耐えるようにします. 3pN以上の引力負荷を適用すると,酵素によるコラーゲンの分解が著しく減速し,機械的なストレスは動物におけるコラーゲンの安定性と長寿を高めることを示唆しています.
科学分野:
- バイオフィジックス 生物物理学
- バイオマテリアル科学 バイオマテリアル科学
- 分子生物学は分子生物学である.
背景:
- コラーゲンは,脊椎動物の重要な構造タンパク質であり,機械的力に抵抗するために不可欠です.
- その持続性は,負荷下での安定性の強化のためのメカニズムを示唆し, antidissipative 行動と呼ばれる.
- 潜在的な機械化学的力スイッチは,酵素分解に対するコラーゲンの感受性を変化させる可能性があります.
研究 の 目的:
- コラーゲンの安定性の機械化学的調節を調査する.
- 機械的な負荷が酵素分解に対するコラーゲンの耐性を影響するかどうかを判断する.
- コラーゲンの長寿における分子力学の役割を明らかにする.
主な方法:
- 大規模な並列,単一分子,機械化学反応アッセイを使用しました.
- 原生組織と復元されたコラーゲン繊維で分解実験を行った.
- クロストリジウムヒストロリチウムによるリコンビナントヒトI型コラーゲンモノメアの酵素分解率を,異なる張力負荷下で測定した.
主要な成果:
- 3pNを超える牽引負荷は,負荷のない対照と比較して,コラーゲンモノメアの酵素分解率を約10倍減少させた.
- 機械的なストレスは,明らかにコラーゲン分子構造の安定性を高めます.
- コラーゲン/酵素動態は,負荷を伴うコラーゲンの保持を好み,負荷に依存する分解プロセスを示す.
結論:
- コラーゲンモノメアの機械的状態は,組織内の長寿命と直接相関しています.
- コラーゲンのストレスの作用による分子安定性は,動物における構造的適応の基本的基盤を提供します.
- このメカニズムにより,動物は機械的ストレス下での材料の配置と負荷を最適化できます.
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