| Popis: |
To obtain gram amounts of the various casein fractions, whole casein dispersed in 3.3 M urea (pH 7.4) containing 77 mg/L dithiothreitol was fractionated at 5°C by ion-exchange adsorption on diethylaminoethyl cellulose, Whatman DE 52, with stepwise salt extraction. Fractions were obtained by successive extraction with .00, .035, .085, .12, and .175 M sodium chloride, which upon further purification by appropriate recycling, yielded the minor β -casein (previously named γ-caseins), κ-caseins, major β -casein, α s2 -caseins, and α s1 -caseins, respectively. |
