初期アミノ酸:コドン 割り当てとコドン:アンチコドン結合の強さ
Meng Su1, Samuel J Roberts1, John D Sutherland1
1MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, U.K.
Journal of the American Chemical Society
|April 27, 2024
まとめ
原始ペプチド合成では,特定のコドン割り当てが利用された可能性がある. アンチコドンループによる家族箱コドンのより緊密な結合は,生命の初期に最初に使用されたものの1つであることを示唆しています.
科学分野:
- 分子生物学
- 生命 研究 の 起源
- 生物化学
背景:
- リボソームは,アミノアシル-tRNAとペプチジル-tRNAを結合することによってペプチド合成を促進する.
- この結合は,mRNAと受容体幹の相互作用によるアンチコドン:コドンのペアリングによるもので,ペプチジルトランスファーゼの中心にある.
研究 の 目的:
- 初期のリボソームペプチド合成における固有のコドン:アンチコドン結合強さの役割を調査する.
- 初期のアミノ酸配分がコドン結合親和性と相関するかどうかを判断する.
主な方法:
- 抗コドン幹のループとコドンを代表する短いオリゴヌクレオチドの間の結合親和度を測定した.
- ファミリーボックスの結合強度とスプリットボックスの結合強さの比較
主要な成果:
- ファミリー・ボックス・コドン:アンチコドンのペアリングは,スプリット・ボックス・ペアリングよりも著しく強い結合を示す.
- 2つのファミリーボックス・アンチコドン・ステム・ループは,スプリットボックス・ペアリングとは異なり,隣接するコドンを同時に結合することができる.
- ファミリーボックスによってコードされたアミノ酸は,初期のシアノスルフィド化学によって生成されたものと一致します.
結論:
- 内在のコドン:アンチコドン結合強さは,ペプチド合成における初期のアミノ酸配分に影響を与えた可能性がある.
- ファミリー・ボックス・コドンは,より緊密に結合し,使用された最も初期のコドンセットを表す可能性があります.
- これは,初期のペプチド合成が,原始化学を通じてアクセス可能な限られたアミノ酸のセットを使用したという仮説を支持する.
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