ダイナミックアロステリーは,酵素の寒さへの適応を促す
Harry G Saavedra1,2, James O Wrabl1,2, Jeremy A Anderson1,2
1Department of Biology, Johns Hopkins University, Baltimore, MD, USA.
Nature
|June 8, 2018
まとめ
生物は酵素の進化的変化によって新しい環境に適応する. この研究は,遠隔の変異が酵素活性にアロステル的に調節し,活性部位の構造を変えることなく,基板の親和性および周回率に影響を与える方法を示しています.
科学分野:
- 進化生物学
- 生物化学
- 酵素運動
背景:
- 生物は進化の過程で 極端な温度などに適応します
- 異なる環境からの酵素オートロジは,触媒速度を維持する適応変異を示します.
- 適応性突然変異は,酵素の活性部位から遠く離れた表面部位でしばしば発生し,アロステル調節に関する疑問を提起する.
研究 の 目的:
- アロステル調節と適応における酵素ダイナミクスの役割を調査する.
- ディスタルシーケンスの変化が 酵素活性を調節する方法を調べる
- 進化の過程で酵素が機能する仕組みを理解する
主な方法:
- エスケリキア・コライアデニラートキナーゼの ディスタル部位に エンジニアリングエントロピー調節変異
- これらの変異が酵素動力学,基質親和,転移率に与える影響を定量的に評価する.
- 主要な酵素パラメータに対する制御の空間的分離を分析する.
主要な成果:
- ダイナミクスに基づくアロステリックチューニングメカニズムが明らかになった.
- LIDドメインの制御基質の相性における変動
- AMP結合ドメインのダイナミック減衰は,酵素の回転に影響します.
- 酵素パラメータの制御における空間的分離が明らかにされた.
結論:
- 酵素の適応は,基底状態の構造を変えることなく,動力学に基づくアロステル調節によって達成できます.
- このメカニズムは,酵素の動態とターンオーバーの関係を理解するための新しいモデルを提供します.
- ダイナミクスに基づく調節は 生物学的機能を微調整するための 潜在的に広範囲にわたる進化的戦略を表しています
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