Preparation and amino acid sequence of human kappa-casein.
Human kappa-casein was prepared from whole casein by successive hydroxyapatite and thiol-Sepharose chromatographies. The primary structure of its 99-residue N-terminal fragment has been determined by sequencing peptides obtained by tryptic and chymotryptic digestions of the whole protein. This fragment overlaps the known sequence of the 65-residue C-terminal fragment. The 158-residue sequence of human kappa-casein was compared to those of goat, ewe, cow and rat kappa-caseins. Only 22% of the residues are identical in homologous positions. The rate of divergence of the 93-residue N-terminal segment (para-kappa-casein) appears to be higher than that of the rest of the molecule.
D000595:Amino Acid Sequence; D000818:Animals; D002364:Caseins / Q000302:isolation & purification* / Q000378:metabolism; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D002918:Chymotrypsin / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006041:Goats; D006801:Humans; D007525:Isoelectric Focusing; D008895:Milk, Human / Q000032:analysis*; D010446:Peptide Fragments; D051381:Rats; D012756:Sheep; D014357:Trypsin / Q000378:metabolism
D002364:Caseins; D010446:Peptide Fragments; D002918:Chymotrypsin; D014357:Trypsin