EFFECT OF METAL IONS ON THE EFFICIENCY OF DNA AMPLIFICATION. IMPLICATIONS FOR NUCLEIC ACID REPLICATION DURING EARLY STAGES OF LIFE

摘要

The emergence of life on Earth was preceded by the accumulation of large amounts of organic biomonomers in the environment. The condensation of these molecules to give rise more complex compounds, such as nucleic acids, probably was a process in which metal ions played a relevant role as catalysts. We have studied the modulation of the current enzymatic replication of nucleic acids in conditions that mimic some of the characteristics of primitive environments. These conditions are: presence of metal ions and nucleotide concentration imbalances. The results obtained show the ability of several of the metal ions assayed to increase the efficiency of nucleic acid replication under unfavourable nucleotide concentrations. In addition, the presence of Co~(2+) increase the error rate of replication. Therefore, it is probable that metal ions, very abundant in primitive environments, could have had a role to accelerate the generation of diversity in ensembles of primitive replicators, facilitating in this way the selection of molecules with more complex capacities.