Fibril and hence the whole muscle. Elastin is a fibrous protein common in various soft tissues, like skin, blood vessels and lung tissue. Each monomer connects with each other, forming a 3D network, with ability to endure over 200% strain before deformation. Keratin is a structural protein mainly found in hair, nails, hooves, horns, quills. Basically keratin is formed by polypeptide chains, which coil into α-helices with sulfur cross-links or bond into β-sheets linked by hydrogen bonding. β-keratin, which is tougher than α-conformation, is more common in birds and reptiles. Resilin is an elastomeric insect protein, consisting of both α-helices and
Translocase of the outer membrane internal targeting signals, not all of which have been identified, and include proteins that take on a β-barrel structure, such as Tom40. Some proteins however, that are targeted to the outer mitochondrial membrane contain a hydrophobic tail domain that anchors the protein to the membrane. The translocase of the outer membrane (TOM) forms a complex made of Tom70, Tom22, and Tom20, along with Tom40, Tom7, Tom6, and Tom5. Tom20 and Tom22 are preprotein receptors, which are responsible for recognition of the cleavable presequence possessed by mitochondrial-targeted proteins. Tom70 is also a preprotein receptor and may recognise some cleavable presequence proteins,