ORIGIN OF LIFE - A HYPOTHESIS FOR THE ORIGIN OF ADAPTOR-MEDIATED ORDERED SYNTHESIS OF PROTEINS AND AN EXPLANATION FOR THE CHOICE OF TERMINATING CODONS IN THE GENETIC-CODE

Life can be defined as a system of self-sustained chemical processes springing from the ordered synthesis of proteins directed by nucleic acids. To the notoriously difficult problem of the origin of this basic process of nucleic acid-directed protein synthesis, a solution of molecular interactions between pentanucleotides and amino acids is given. A particular conformation of a pentanucleotide forms a double sided template, with its inside capable of nestling an amino acid; the outside acts as an adaptor to a codon triplet on long-chain nucleic acids. This serves as a primitive decoding system. An important aspect of this postulate is that a dynamic interaction is triggered by this decoding system through which amino acids are brought to juxtaposition facilitating peptide bond formation. Almost all the important and unique features of contemporary protein-synthesizing machinery are seen to be a direct and natural consequence of this postulate. The emergence of the termination codons also fits in, as a natural consequence of this molecular mechanism.