Patent ID: 8912310

Claim:
An environmentally responsive polypeptide comprising at least ten repeats of an amino acid sequence Z 1 PXGZ 2 Z 3 Z 4 Z 5 , wherein P is proline, G is glycine, X is from 0 to 4 amino acids that are not proline or glycine, and Z 1 , Z 2 , Z 3 , Z 4 and Z 5 are each an amino acid and Z 2 is optionally absent, wherein the amino acid sequence comprises (i) an arginine, (ii) serine or an amino acid selected from aspartate and glutamate, or both serine and aspartate or glutamate, and (iii) at least one hydrophobic residue selected from valine, leucine, isoleucine, histidine, tyrosine, tryptophan and alanine, wherein the polypeptide upon stimulation undergoes a conformational change that is accompanied by aggregation.