α-Crystallin was isolated from calf lenses and purified by repeated precipitation at its isoelectric point. Electrophoretic mobilities, intrinsic viscosities, and partial specific volumes were determined at pH's 2.0, 7.7, and 9.1, ionic strengths 0.1, 0.2, and 0.3, respectively. Sedimentation studies were performed at pH 2.0, μ 0.10, and at pH 9.1, μ 0.30. A light-scattering study was done at pH 7.7, μ 0.20. The viscosity and sedimentation studies at pH 2.0 indicate an unfolding of the protein ultimately leading to dissociation. This dissociation is not evident in electrophoretic studies, which show a single boundary at different pH's and ionic strengths. Molecular weights and dimensions have been calculated from sedimentation, viscosity, and partial specific volume data at pH 9.1, μ 0.30.The physicochemical properties of calf α-crystallin have been compared with those of ox α-crystallin. The electrophoretic and sedimentation studies indicate similar degrees of homogeneity of the α-crystallin preparations obtained from the two sources. It appears from these studies that calf α-crystallin is larger and more asymmetric than ox α-crystallin at pH's 2.0 and 9.1, ionic strengths 0.10 and 0.30, respectively. At pH 7.7, μ 0.20, calf α-crystallin, although having nearly the same size, is definitely more asymmetric than ox α-crystallin.
Assembly of fibrin. A light scattering study.
