ENZYMATIC DEPHOSPHORYLATION OF OVALBUMIN AND PLAKALBUMIN

It has been shown by the work presented in this paper that it is possible to carry out a stepwise dephosphorylation of ovalbumin. With the aid of a prostate phosphatase that attacks only one of the two phosphorus-containing groups in the major component, A₁, of ovalbumin, a protein, A₂, containing 1 atom of phosphorus per mole has been prepared. Further dephosphorylation with an enzyme of intestinal origin gives a phosphorus-free ovalbumin, A₃. Plakalbumin has been similarly dephosphorylated to give P₂ and P₃. Significant changes in the electrophoretic mobility accompany each dephosphorylation step. This, together with the phosphorus content of the proteins and the crystal form, has been used to characterize and study the five modifications of ovalbumin thus produced.