タイロシンキナーゼ活性を持つDNA触媒
Shannon M Walsh1, Amit Sachdeva, Scott K Silverman
1Department of Chemistry, University of Illinois at Urbana-Champaign , 600 South Mathews Avenue, Urbana, Illinois 61801, United States.
Journal of the American Chemical Society
|September 27, 2013
まとめ
デオキシリボ酵素として知られるDNA酵素は,ペプチドのチロシン残基をリン酸化することができます. この発見はDNAの触媒的能力を拡大し,生化学研究と応用のための新しい道を開く.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- カタリシス カタリシス カタリシス
背景:
- DNA触媒 (デオキシリボ酵素) は,その多様な酵素的機能のためにますます認識されています.
- リン酸化は,生物学的システムにおける重要な翻訳後の変化であり,主にタンパク質キナーゼによって媒介される.
研究 の 目的:
- デオキシリボジームがペプチド内のチロシン残基のリン酸化を触媒化する可能性を調査する.
- タイロシンリン酸化を行うことができるDNA触媒を特定し,特徴づけること.
主な方法:
- ランダムな配列のDNAプールからデオキシリボジームを進化させるために,インビトロ選択が採用されました.
- タイロシン残留を含むペプチド基板は,リン酸化活性をスクリーニングするために使用されました.
- 明らかにKmを含む酵素動態は,特定されたデオキシリボジームのために決定されました.
主要な成果:
- ヘクサペプチドのチロシン残基にフォスフォリル基を転送できるデオキシリボ酵素が成功裏に特定されました.
- これらのDNA触媒には特定の金属イオン,主にZn2+としばしばMn2+が必要です.
- 特定されたデオキシリボ酵素は,セリンリン酸化よりもチロシンに高い選択性を持ち,隣接アミノ酸に低い選択性を示しています.
結論:
- DNAは,ペプチド基板上のチロシン残基をリン酸化する基本的な触媒能力を持っています.
- ティロシンキナーゼデオキシリボジームの発見は,既知のDNA酵素機能のレパートリーを拡大する.
- これらの発見は,合成生物学とバイオテクノロジーの新種のDNAベースの触媒の可能性を開きます.
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