The invention provides substantially pure abductin protein and polypeptides, polypeptides composed of multiple repeats of the glycine-rich repeat sequences of abductin, and hybrid polypeptides containing an abductin polypeptide linked to another protein or polypeptide, e.g., an elastin or fibroin (silk) polypeptide, as well as nucleic acids encoding these polypeptides. The abductin polypeptides and their derivatives can be used in the manufacture of a broad range of biomaterials ranging from light-weight durable fabric for clothing to matrices useful for human tissue and organ prostheses.