A Simple Generic Model of Elastin–Like Polypeptides with Proline Isomerization

A generic model of elastin–like polypeptides (ELP) is derived that includes proline isomerization (ProI). As a case study, conformational transition of a –[valine–proline–glycine–valine–glycine]– sequence is investigated in aqueous ethanol mixtures. While the non–bonded interactions are based on the Lennard–Jones (LJ) parameters, the effect of ProI is incorporated by tuning the intramolecular 3– and 4–body interactions known from the underlying all–atom simulations into the generic model. One of the key advantages of such a minimalistic model is that it readily decouples the effects of geometry and the monomer–solvent interactions due to the presence of ProI, thus gives a clearer microscopic picture that is otherwise rather nontrivial within the all–atom setups. These results are consistent with the available all–atom and experimental data. The model derived here may pave the way to investigate large scale self–assembly of ELPs or biomimetic polymers in general.