Changes in the shape and surface hydrophobicity of ovalbumin during its transformation to s-ovalbumin.

Intrinsic viscosity, Stokes radius and the hydrophobic coefficient of Keshavarz and Nakai [Biochim.Biophys.Ada, SI6, 269 (1979)] were measured to compare the shape and surface hydrophobicity of ovalbumin and ^-ovalbumin.Both the intrinsic viscosity and Stokes radius of sovalbumin were smaller than those of ovalbumin, which suggests that the configuration of sovalbumin became more compact during the ovalbumin-s-ovalbumin transformation.The hydrophobic coefficient of s-ovalbumin was larger than that of ovalbumin, which suggests that the surface hydrophobicity of s-ovalbumin was larger than that of ovalbumin.Further, these properties were measured for ovalbumin samples obtained at various stages of ovalbumin-s-ovalbumin transformation.Changes in the shape and surface hydrophobicity of ovalbumin were not found in the first stage of ovalbumin-s-ovalbumin transformation.They changed rapidly in the last stage of the ovalbumin-5-ovalbumin transformation.