Department of Chemistry, Institute for Chemical Epigenetics (ICE-M), Ludwig-Maximilians-Universität (LMU) München, Butenandtstrasse 5-13, 81377, Munich, Germany.
Angew Chem Int Ed Engl. 2024 May 6;63(19):e202319235. doi: 10.1002/anie.202319235. Epub 2024 Apr 5.
The world in which we live is homochiral. The ribose units that form the backbone of DNA and RNA are all D-configured and the encoded amino acids that comprise the proteins of all living species feature an all-L-configuration at the α-carbon atoms. The homochirality of α-amino acids is essential for folding of the peptides into well-defined and functional 3D structures and the homochirality of D-ribose is crucial for helix formation and base-pairing. The question of why nature uses only encoded L-α-amino acids is not understood. Herein, we show that an RNA-peptide world, in which peptides grow on RNAs constructed from D-ribose, leads to the self-selection of homo-L-peptides, which provides a possible explanation for the homo-D-ribose and homo-L-amino acid combination seen in nature.
我们生活的世界是手性的。构成 DNA 和 RNA 骨架的核糖单元都是 D 构型，而构成所有生物蛋白质的氨基酸在α碳原子上都具有全 L-构型。α-氨基酸的手性对于将肽折叠成明确的和功能的 3D 结构是必不可少的，而 D-核糖的手性对于形成螺旋和碱基配对至关重要。自然界为什么只使用编码的 L-α-氨基酸这个问题尚未得到解答。在这里，我们表明，一个由 D-核糖构成的 RNA-肽世界，其中肽在 RNA 上生长，导致同型 L-肽的自我选择，这为自然界中所见的同型 D-核糖和同型 L-氨基酸组合提供了一种可能的解释。
