Beta-keratin

β-keratin or beta-keratin (not to be confused with β-carotene) is in contrast to alpha-keratin, a fibrous protein rich in alpha helices, rich in stacked β pleated sheets.

β-keratin adds much more rigidity to reptilian skin than alpha-keratin does to mammalian skin.

β-keratin is impregnated into the stratum corneum of the reptilian skin, providing waterproofing and the prevention of desiccation. Bird's Beaks, claws and feathers are also made from β-keratin