Studies of the proteins, peptides and free amino acids of mature bovine enamel.

1. The organic matrix of enamel from erupted bovine teeth has been found to be composed mostly of small peptides containing principally aspartic acid, glycine, glutamic acid and serine. 2. A small amount of higher-molecular-weight components has been isolated by various procedures. One non-diffusible fraction was found to be heterogeneous in the ultracentrifuge, and composed principally of material that by gel filtration indicated a molecular weight greater than 30000. These components were largely carbohydrate in nature (glycoproteins and glycopeptides), containing only small amounts of amino acids.