Enzymatic solubilization of insoluble proteins at neutral pH.

Insoluble epidermal proteins (possibly keratin), previously considered inert to enzyme action, were solubilized by either trypsin or chymotrypsin. Cleavage of the disulfide bonds prior to enzymatic action is not necessary. In addition, the enzymatic action on intact epidermis is not influenced by the presence or absence of endogenous lipids, soluble proteins, peptides, or amino acids. Solubilization of epidermal protein by chymotrypsin is inhibited by the supernatant solution of the homogenized epidermis.