Revealing condensation affinities of nucleic bases through atomistic simulation of model RNA-peptide mixtures.

Bio-molecular condensation of proteins and nucleic acids has emerged as a key mechanism underlying the formation of membraneless cellular bodies. The thermodynamic driving force of condensation is often rationalized from the perspective of polymeric liquid-liquid phase separation and classical mean-field theories. However, the environment of bio-molecular condensates often deviates from the mean-field picture and requires a more detailed microscopic model of amino acid-nucleic base interactions within condensates. In this work, we set up model peptide nucleo-base mixtures, which allows one to quantify the affinity of different residue-base pairs under various external and internal conditions, including salt, stoichiometry, density, and temperature.