IDPs can be characterized by the lack of stable well-defined native structures of folded proteins , and amino acid compositions biased towards a high fraction of charged and polar residues, secondary-structure disrupters such as proline and glycine, and a low amount of bulky hydrophobic amino acids . It is believed the multivalent attractive interaction between side chains may give rise to favorable energetic gain that is responsible for counteracting the entropic loss during LLPS , and the phase behaviours of IDPs can be specifically encoded in their protein sequences .