Abstract
AbstractAt the end of the planetesimal infall on the surface of the primitive earth, hot dry beaches might have been useful for the formation of various activated monomers and oligomers (peptides and small RNAs). We discuss the possibility that a small system composed of small RNAs (∼ 10 mers) and dipeptides might have mimicked the contemporary biosystem, based on experimental results suggesting the presence of previously overlooked weak but specific interactions between three bases and one amino acid (of genetic code type) and also those between a dipeptide and a biosubstrate (of ligase, transferase, hydrolase, lyase, isomerase and dehydrogenase type). The Kms obtained for these dipeptide enzymes were of the order of 1M, in accord with the association constant for the binding of guanosine to cytocine in water. In this oligomer world, the genotype and phenotype evolution was closely coupled, resulting in a very rapid rate of evolution.
Publisher
Cambridge University Press (CUP)