Physical non-equilibria for prebiotic nucleic acid chemistry

Alan Ianeselli, Annalena Salditt, Christof Mast, Barbara Ercolano, Corinna L. Kufner, Bettina Scheu and Dieter Braun

Nature Reviews Physics https://doi.org/10.1038/s42254-022-00550-3

Abstract

The prebiotic replication of DNA and RNA is a complex interplay between chemistry and the environment. Factors that have direct and indirect effects on prebiotic chemistry include temperature, concentration of monovalent and bivalent ions, the pH of water, ultraviolet irradiation and the presence of gaseous CO₂. We discuss various primordial conditions to host the first replication reactions on the early Earth, including heated rock pores, hydrothermal vents, evaporating water ponds, freezing–thawing ice compartments, ultraviolet irradiation and high CO₂ concentrations. We review how the interplay of replication chemistry with the strand separation and length selectivity of non-equilibrium physics can be provided by plausible geo-environments. Fast molecular evolution has been observed over a few hours in such settings when a polymerase protein is used as replicator. Such experimental findings make us optimistic that it will soon also be possible to probe evolution dynamics with much slower prebiotic replication chemistries using RNA. Our expectation is that the unique autonomous evolution dynamics provided by microfluidic non-equilibria make the origin of life understandable and experimentally testable in the near future.