First arrived, first served: competition between codons for codon-amino acid stereochemical interactions determined early genetic code assignments

Prebiotic Synthesis of ATP: A Terrestrial Volcanism-Dependent Pathway

“…The inheritance of these proteins remains a problem because how RNA coding proteins and self-replication still does not have a solution. Recent studies showing the preference for interactions between different oligonucleotides and amino acids [ 86 ], as well as the modified nucleotides which are easier to be ligated [ 87 ], have shed new light on these problems. Moreover, the homochirality of RNA and protein, which is a significant issue in the origin of life, may also be achieved during the replication of RNA and ribozyme catalyzed peptide synthesis [ 88 , 89 , 90 ].…”

Theoretical minimal RNA rings mimick molecular evolution before tRNA-mediated translation: codon-amino acid affinities increase from early to late RNA rings

“…Accordingly, such associations observed in modern genes and their proteins would be remnants of a more ancient translation mechanism lacking tRNAs and ribosome, based on direct physicochemical interactions between codon and amino acid. Codon-amino acid assignments in the genetic code would have resulted from these direct codonamino acid interactions [96,97], which would also explain biases for codon-amino acid contacts in the ribosome ( [29], and herein Figure 2).…”