Genetic Polymorphism in Caseins of Cow's Milk. VI. Amino Acid Composition of αs1-Caseins A, B, and C

Abstract

The amino acid composition of highly purified preparations of the genetically controlled variants of αs1-casein, A, B, and C has been determined. B and C are virtually identical in composition, the only significant difference being that C contains one more glycine residue per mole than B. The data suggest that in B the missing glycine might be replaced by glutamic acid. The differences between A and the other variants are numerous and more substantial and, at present, cannot be accounted for in terms of single amino acid substitutions. © 1965, American Dairy Science Association. All rights reserved.