INFLUENCE OF GLYCOSYLATION ON MICELLE-STABILIZING ABILITY AND BIOLOGICAL PROPERTIES OF C-TERMINAL FRAGMENTS OF COWS KAPPA-CASEIN

C-terminal fragment of bovine kappa-casein contains glycosidic residue s. There are several glycoforms of kappa-casein containing different k inds and numbers of glycosidic residues. Such heterogeneity affects pr operties of this protein and its fragments. The C-terminal fragment of cow's kappa-casein (residues: 106-169) is the main factor stabilizing casein micelles. Glycosidic moieties connected to this fragment enhan ce the ability of kappa-casein to stabilize micelles and also the resi stance of this protein to the action of proteolytic enzymes and high t emperature in simple model systems. kappa-Casein, its C-terminal fragm ent (macropeptide or glycomacro-peptide) or products of its proteolysi s can inhibit proliferation of lymphocytes B, binding Cholera toxin to its receptor, hemagglutination of influenza virus, adhesion of bacter ia to cell surface, acid secretion in the stomach, as well as stimulat e the release of cholecystokinin in the intestinal cells and the growt h of Lactococcus lactis bacteria. Glycosidic moieties may act as an in formation carrier enabling recognition of compounds (e.g. components o f cells) interacting with kappa-casein, glycomacropeptide or its fragm ents. Copyright (C) 1996 Published by Elsevier Science Limited.