Probable Identification of γ, TS-, R- and S-Caseins as Fragments of β-Casein

From the results of amino acid analysis, molecular weight determinations, peptide mapping, and end-group analysis, it was believed that bovine γ-, TS-, R- and S-caseins might be pieces of different sizes of the β-casein molecule. Determination of the sequence of the first 10 to 15 amino acid residues at the n-terminal part of these proteins by a sequencer lends credence to the hypothesis because the sequences fit, at appropriate locations, the partial amino acid sequence of β-casein worked out by Ribadeau Dumas, Grosclaude and Mercier.