CHROMATOGRAPHIC SEPARATION OF PHOSVITIN, α- AND β-LIPOVITELLIN OF EGG YOLK GRANULES ON TEAE-CELLULOSE

Abstract

The two components of lipovitellin and the three major components of yolk granules, phosvitin, α- and β-lipovitellin, have been separated by gradient elution chromatography on TEAE-cellulose. A 0.2 M phosphate buffer (pH 6.8) had the necessary ionic strength to dissolve these proteins and when applied in this solvent all components except β-lipovitellin were retained by the column. A linear gradient of ionic strength (limit buffer 0.2 M phosphate plus 0.5 M NaCl) was used to remove the other components. Recovery was essentially complete and the composition and properties of the individual components were similar to those obtained by previous chromatographic methods that gave only partial recovery. An additional component eluted after α-lipovitellin and before phosvitin, previously observed in Dowex-1 separations, was also observed by the present method. The composition, sedimentation behavior, and absorption spectra of this component indicate that it is a soluble complex of phosvitin and lipovitellin. When granules are dissolved in alkaline solvents (pH 9.4) of low ionic strength (0.05), phosvitin is not evident as a separate component during ultracentrifugation, but appears as the ionic strength is increased.