The Chemoton: A Model for the Origin of Long RNA Templates.

How could genomes have arisen? Two models based on Ganti's Chemoton are presented which demonstrate that under increasingly realistic assumptions, template replication is facilitated without the need of enzymes. It can do this because the template state is stoichiometrically coupled to the cell cycle. The first model demonstrates that under certain kinetic and environmental conditions there is an optimal template length, i.e. one which facilitates fastest replication of the Chemoton. This is in contradiction to previous findings by Csendes who claimed that longer templates allowed more rapid replication. In the second model, hydrogen bonding, phosphodiester bonding and template structure is modeled, so allowing dimer and oligomer formation, hydrolysis and elongation of templates. Here, monomer concentration oscillates throughout the cell cycle so that double strands form at low monomer concentrations and separate at high monomer concentrations. Therefore, this simulation provides evidence that a protocell with Chemoton organization is a plausible mechanism for the formation of long templates, a notorious problem for studies of the origin of life.