title: Porcine alpha-lactalbumin A and B.
abstract: The occurrence of the 'whey' protein, alpha-lactalbumin, in pig (Sus scrofus) milk samples from 904 sows is examined. A semi-discontinuous buffer system has been developed to detect the existence of genetic polymorphism. There are two homozygous variants, designated A and B. Both variants are isolated and it is shown by peptide and sequencing studies that the A variant differs from the B variant by having an Arg residue substituted for the Lys residue at the N-terminus of the molecule. The sequence of the first thirty residues is determined and compared with those of related alpha-lactalbumins.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D005260:Female; D014644:Genetic Variation; D006720:Homozygote; D007768:Lactalbumin / Q000235:genetics* / Q000302:isolation & purification; D008892:Milk / Q000032:analysis*; D010446:Peptide Fragments; D011110:Polymorphism, Genetic; D011247:Pregnancy; D013045:Species Specificity; D013552:Swine / Q000378:metabolism*
chemical_list: D010446:Peptide Fragments; D007768:Lactalbumin