Keratin vs. Kreatin — Which is Correct Spelling?

Keratin () is one of a family of fibrous structural proteins known as scleroproteins. α-Keratin is a type of keratin found in vertebrates.

A fibrous protein forming the main structural constituent of hair, feathers, hoofs, claws, horns, etc.

Any of a class of filamentous proteins that are abundant in the cytoskeleton of vertebrate epithelial cells and are the main constituents of the outer layer of skin and tough epidermal structures such as hair, nails, hooves, feathers, and claws.

Material composed principally of keratin proteins.

(protein) The protein of which hair and nails are composed.

A sulfur-containing fibrous protein constituting the main structural protein of hard epidermal tissues, such as horn, hair, feathers, nails, claws, hoofs, and the like. It is an insoluble substance, and, unlike elastin, is not dissolved even by gastric or pancreatic juice. By decomposition with sulphuric acid it yields leucine and tyrosine plus various other acid-stable amino acids. The amino acid composition varies, but it usually has a high percentage of cystine, which stabilizes and insolubilizes the protein by forming intrachain linkages. A softer form of keratin is present in the epidermis and whalebone. Called also epidermose.

A fibrous scleroprotein that occurs in the outer layer of the skin and in horny tissues such as hair feathers nails and hooves