The number of polypeptide chains in the rod domain of bovine epidermal keratin.

The physical properties of the alpha-helix enriched particle obtained by limited proteolysis of epidermal keratin have been examined. Molecular weights in benign and dissociating solvents, hydrodynamic measurements and chemical cross-linking experiments indicate that the particle has four polypeptide chains. It is proposed that the helical particle is assembled from a pair of two-stranded alpha-helical ropes.