Open AccessThis article is
- freely available
Molecular Basis for Chiral Selection in RNA Aminoacylation
Department of Biological Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
Research Institute for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
Received: 24 May 2011; in revised form: 29 June 2011 / Accepted: 18 July 2011 / Published: 22 July 2011
Abstract: The chiral-selective aminoacylation of an RNA minihelix is a potential progenitor to modern tRNA-based protein synthesis using l-amino acids. This article describes the molecular basis for this chiral selection. The extended double helical form of an RNA minihelix with a CCA triplet (acceptor of an amino acid), an aminoacyl phosphate donor nucleotide (mimic of aminoacyl-AMP), and a bridging nucleotide facilitates chiral-selective aminoacylation. Energetically, the reaction is characterized by a downhill reaction wherein an amino acid migrates from a high-energy acyl phosphate linkage to a lower-energy carboxyl ester linkage. The reaction occurs under the restriction that the nucleophilic attack of O, from 3′-OH in the terminal CCA, to C, from C=O in the acyl phosphate linkage, must occur at a Bürgi-Dunitz angle, which is defined as the O–C=O angle of approximately 105°. The extended double helical form results in a steric hindrance at the side chain of the amino acid leading to chiral preference combined with cation coordinations in the amino acid and the phosphate oxygen. Such a system could have developed into the protein biosynthetic system with an exclusively chiral component (l-amino acids) via (proto) ribosomes.
Keywords: homochirality; amino acid; RNA; aminoacylation; stereochemistry; extended double helix; origin of life
Article StatisticsClick here to load and display the download statistics.
Notes: Multiple requests from the same IP address are counted as one view.
Cite This Article
MDPI and ACS Style
Tamura, K. Molecular Basis for Chiral Selection in RNA Aminoacylation. Int. J. Mol. Sci. 2011, 12, 4745-4757.
Tamura K. Molecular Basis for Chiral Selection in RNA Aminoacylation. International Journal of Molecular Sciences. 2011; 12(7):4745-4757.
Tamura, Koji. 2011. "Molecular Basis for Chiral Selection in RNA Aminoacylation." Int. J. Mol. Sci. 12, no. 7: 4745-4757.