Elastic proteins occur in a wide range of biological systems where they have
evolved to fulfill precise biological roles. The best known include proteins in
vertebrate muscles and connective tissues, such as titin, elastin, fibrillin and
spider silks. Interest in elastomeric proteins is currently high for several
reasons. Firstly, they have biological and medical significance, particularly in
human disease. Secondly, the unusual properties of proteins such as spider silks
provide opportunities to develop novel materials. Thirdly, the development of
scanning probe microscopy makes it possible to study structures and
biomechanical properties of these proteins at the single molecule level.