Noun
A nitrogenous substance, or mixture of substances, containing sulphur in a loose state of combination, and forming the chemical basis of epidermal tissues, such as horn, hair, feathers, 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 leucin and tyrosin, as does albumin. Called also epidermose.
Source: Webster's dictionaryFibrous proteins such as keratin or the "stalks" of myosin or kinesin often adopt coiled-coil structures, as do several dimerizing proteins. Source: Internet
Alcohol (denatured) is added to allow for quicker drying time, and the humectants include dipropylene glycol, betaine and hydrolyzed keratin to add a protective, water-absorbing film layer. Source: Internet
During the process of epithelial differentiation, cells become cornified as keratin protein is incorporated into longer keratin intermediate filaments. Source: Internet
For example, mouse thymic epithelial cells (TECs) are known to react with antibodies for keratin 5, keratin 8, and keratin 14. These antibodies are used as fluorescent markers to distinguish subsets of TECs in genetic studies of the thymus. Source: Internet
Baleen whales have bristles made of keratin instead of teeth. Source: Internet
However, beta sheets are also found in α-keratins.) citation The baleen plates of filter-feeding whales are made of keratin. Source: Internet