Beta-keratin Beta-keratin β-keratin or beta-keratin is a member of a structural protein family found in the epidermis of reptiles and birds . β-keratins were named so because they are components of epidermal stratum corneum rich in stacked β pleated sheets, in contrast to alpha-keratins, intermediate-filament proteins also found in stratum corneum and rich in alpha helices. Because the accurate use of the term "keratin" is limited to the alpha-keratins, the term "beta-keratins" in recent works is replaced by "corneous beta-proteins" or "keratin-associated beta-proteins". β-keratins add much more rigidity to reptilian skin than alpha-keratins alone do to mammalian skin. β-keratins are impregnated
Collagen of the skeleton. The triple helical structure of collagen prevents it from being broken down by enzymes, it enables adhesiveness of cells and it is important for the proper assembly of the extracellular matrix. Collagen scaffolds are used in tissue regeneration, whether in sponges, thin sheets, or gels. Collagen has the correct properties for tissue regeneration such as pore structure, permeability, hydrophilicity, and being stable in vivo. Collagen scaffolds are also ideal for the deposition of cells such as osteoblasts and fibroblasts, and once inserted, growth is able to continue as normal in the tissue. Collagens are widely employed in