The effect of configurational complexity in hetero-polymers on the coil-globule phase transition

The coil-globule transition of hetero-polymer chains is studied here. By means of extensive Molecular Dynamics simulations, we show that the transition is directly linked to the complexity of the chain, which depends on the number of chemical species defined in the environment and the location of the binding sites along the polymer. In addition, when the number of species increases, we find that the distribution of binding sites plays an important role in triggering the transition, beyond the standard control parameters of the polymer model, i.e. binders concentration and binding affinity. Overall, our results show that by increasing the system complexity new organizational layers emerge, thus allowing a more structured control on the polymer thermodynamic state. This can be potentially applied to the study of chromatin architecture, as such polymer models have been broadly used to understand the molecular mechanisms of genome folding.