RNA-Templated Peptide Bond Formation Promotes L-Homochiralty


2024-02-26

Ewa Węgrzyn, Dr. Ivana Mejdrová, Dr. Felix M. Müller, Dr. Milda Nainytė, Dr. Luis Escobar, Prof. Dr. Thomas Carell

Angewandte Chemie, Volume 63, Issue 19, e202319235, 2024

https://doi.org/10.1002/anie.202319235

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.