Plasmin treated /3-casein

Figure 9. Radiochemical and protein analysis of column fractions after hydroxyapatite column chromatography of plasmin-treated (3-casein for various reaction times , total activity or specific activity, Fraction 1 M, total activity, Fraction 2 , specific activity, residual /3-casein O, total protein, Fraction 1. Values for total protein and total activity have been adjusted to correspond to trie same amount of total protein (21.92 mg) applied to each column (28).

Figure 6. DEAE-cellulose chromatography of plasmin-treated H-/3-C admixed with whole casein.

Figure 8. Hydroxyapatite chromatography of plasmin-treated 6-casein. The P-casein (110 mg) containing 1.62 fiCi M-P-C was incubated with plasmin and one-fifth of the reaction mixture was withdrawn at t — 0, 20, 30, 40 and 70 min. Samples were dissolved in 2.0-mL column buffer (lOmM Na2HPOi-NaHsPOi, pH 6.8, containing 6M urea) and a known amount (90-100% of each) was applied to columns of hydroxyapatite (1.6 X 10 cm) equilibrated with the same buffer. Columns were eluted at a flow rate of 20 mL/h with column buffer (40 mL) followed by 300 mM Na HPOi,-NaH2POi pH 6.8, containing 6M urea (110 mL) 5.0 mL fractions were collected. The profile shown is for a reaction time of 40 min (28).

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