エシェリキア・コライのRepヘリケーズ-DNA結合に対する核酸コファクターのアロステリック効果
1Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110.
まとめ
Escherichia coli RepヘリケーゼはDNA結合時に二酸化し,核酸コファクターがDNA相互作用に影響を与えます. このメカニズムは,DNAの複製と解き放ちにおいて極めて重要です.
科学分野:
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
- 遺伝学 遺伝学とは
背景:
- Escherichia coli Repヘリケーゼは,複製中の二重DNAの解き放たれに不可欠です.
- 機能酵素は,DNA結合時に形成されるダイマーであり,各プロトメアは単一鎖または二重鎖DNAを結合することができる.
研究 の 目的:
- DNA結合とDNA誘発のRep二分化のエネルギー学を定量的に研究する.
- 核酸コファクターであるアデノシン・ディホスファート (ADP) とアデノシン・トリホスファート (ATP) アナログAMPP (NH) Pがこれらのプロセスに及ぼす影響を調査する.
主な方法:
- DNA結合とRep二分化の定量分析.
- ADPと非水解性ATPアナログであるAMPP (NH) Pを核酸コファクターとして使用する.
主要な成果:
- 核酸コファクターは,RepヘリゼのDNA結合に有意なアロステリック効果を発揮する.
- ADP結合はRepジマーを促進し,両方のプロトマーが単一鎖DNAを結合する.
- AMPP(NH) P結合は,単一鎖および二重鎖DNAを同時に結合するRepダイマーを好みます.
結論:
- 二次元のRepヘリケーズによるDNA解き放出のためのローリングモデルが提案されています.
- ヘリカース転位はATP結合に結合し,ATP水解は,触媒サイクル毎に複数のDNA塩基対の解き放たれを誘導する.
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