Further characterization of milk pyroglobulin.

Milk pyroglobulin was capable of passing through the "Visking" 8/32 cellulose membrane, when dialysed against deionized water but not against saline. Gel filtration analysis of the protein suggested its dissociation into subunit molecules in deionized water. Amino acid composition revealed high contents of proline, glutamic acid, valine and leucine. The protein possessed a biological activity to increase the permeability of skin vessels when injected intradermally. The colostral whey which was experimentally freed from heat-coagulable substances contained as major components proteins which are antigenically related to the pyroglobulin.