  Elastin-like polypeptides (ELPs) undergo a sharp solubility transition from
low temperature solvated phases to coacervates at elevated temperatures, driven
by the increased strength of hydrophobic interactions at higher temperatures.
The transition temperature, or 'cloud point', critically depends on sequence
composition, sequence length, and concentration of the ELPs. In this work, we
present a temperature-dependent, implicit solvent, sequence-specific
coarse-grained (CG) simulation model that reproduces the transition
temperatures as a function of sequence length and guest residue identity of
various experimentally probed ELPs to appreciable accuracy. Our model builds
upon the self-organized polymer model introduced recently for intrinsically
disordered polypeptides (SOP-IDP), and introduces a semi-empirical functional
form for the temperature-dependence of hydrophobic interactions. In addition to
the fine performance for various ELPs, we demonstrate the ability of our model
to capture the thermal compactions in dominantly hydrophobic intrinsically
disordered polypeptides (IDPs), consistent with experimental scattering data.
With the high computational efficiency afforded by the CG representation, we
envisage that the model will be ideally suited for simulations of large-scale
structures such as ELP networks and hydrogels, as well as agglomerates of IDPs.
