Sequence Length\nControls Coil-to-Globule Transition\nin Elastin-like Polypeptides

It appeared certain that elastin condensates retain liquid-like\nproperties. However, a recent experimental study demonstrated that\ntheir aggregate states might depend on the length of hydrophobic domains.\nTo gain microscopic insight into this behavior, we employ atomistic\nmodeling to assess the conformational properties of hydrophobic elastin-like\npolypeptides (ELPs). We find that short ELPs always remain in coil-like\nconformations, while the longer ones prefer globule states. While\nthe former engages in intrapeptide hydrogen bonds temporarily, retaining\ntheir liquid-like properties, the latter forms hundreds of nanosecond-long\nintrapeptide hydrogen bonds attributed to ordered secondary structure\nmotifs. Our work demonstrates that the sequence length modulates the\nmaterial properties of elastin condensates.