Isolation of κ-Casein-Like Proteins from Milks of Various Species

Abstract

κ-Casein-like proteins were isolated from the milks of cow, goat, reindeer, horse, rat, and rabbit. When treated with rennin, all of the isolated κ-casein components yielded para-κ-casein-like bands on gel electrophoresis. The rate of cleavage of these components with rennin was determined by measuring material soluble in trichloroacetic acid (macropeptide). The curves were characteristic of a limited, specific attack by rennin on these proteins. The goat and reindeer κ-caseins were nearly as sensitive to cleavage by rennin as bovine κ-casein, but the cleavage of horse, rat, and rabbit κ-casein-like components was much slower. © 1976, American Dairy Science Association. All rights reserved.