The effect of extraction procedures on sedimentation properties of epidermal proteins.

In previous investigations (1, 2) proteins extracted from mammalian epidermis by solvents such as water, urea, and sodium lauryl sulfate were studied by the technique of electrophoresis. The current presentation consists of further characterization of epidermal proteins by means of sedimentation rates obtained by ultracentrifugation analysis. Mercer and Olofsson (3) have investigated a urea extract of the prekeratinous layers of epidermis in order to amplify the knowledge gained from techniques (e.g., x-ray diffraction) applicable to the intact epidermis. More distantly related researches regarding soluble derivatives of wool and feather keratin are those of Mercer and Olofsson (4) and of Woodin (5, 6). An excellent introduction concerning some of the chemical and physical properties of epidermal proteins will be found in the publications of Rudall (7). Since primary neoplasms can readily be produced in mammalian epidermis, it is a highly suitable tissue for making comparative physicochemical studies of the normal and malignant states. This work involves normal tissue proteins and serves as a basis for future comparative research on malignant tissue.