| http://purl.uniprot.org/keywords/416 | http://www.w3.org/2000/01/rdf-schema#comment | "Fibrous proteins rich in cysteine and the chief constituent of horn, nails, hair, epidermis and feathers. Two major conformational groups have been characterized, alpha-keratin, whose peptide backbone forms an alpha-helix, and beta-keratin, whose backbone forms a zigzag or pleated sheet structure."xsd:string |