Comparison of Similar Protein Components Isolated from Wool and Wool Roots

Abstract

Soluble derivatives of wool and wool-root proteins have been extracted by reduction with mercaptoethanol in the presence of 8M urea followed by alkylation with acrylonitrile. Using chromatography on DEAE-cellulose, followed by gelfiltration on Sephadex, one of the major low-sulphur proteins present in the extract has been isolated in a pure state as determined by starch-gel electrophoresis. Such pure proteins were isolated from extracts of wool and wool roots taken from the same animal. Proteins from these two sources were then compared on the basis of amino acid composition and peptide maps prepared from tryptic digests of them. The results show that small but significant differences do exist between the wool and wool-root proteins. Oomparisons of the protein from different wools show that differences also occur here. It is concluded that small changes must occur in the protein composition during the keratinization process.