Symmetry (Jun 2010)

Experimental Test of L- and D-Amino Acid Binding to L- and D-Codons Suggests that Homochirality and Codon Directionality Emerged with the Genetic Code

  • Robert Root-Bernstein

DOI
https://doi.org/10.3390/sym2021180
Journal volume & issue
Vol. 2, no. 2
pp. 1180 – 1200

Abstract

Read online

L-amino acids bind preferentially to their D-codons, but almost nothing is known about whether D-amino acids correspondingly prefer L-codons, or how codon directionality affects amino acid binding. To investigate these issues, two D-RNA-oligonucleotides having inverse base sequences (D-CGUA and D-AUGC) and their corresponding L-RNA-oligonucleotides (L-CGUA and L-AUGC) were synthesized and their affinity determined for Gly and eleven pairs of L- and D-amino acids. The data support the hypothesis (Root-Bernstein, Bioessays 2007; 29: 689–698) that homochirality and codon directionality emerged as a function of the origin of the genetic code itself. Further tests involving amplification methods are proposed.

Keywords