Yeh Y, Iwai S, Feeney R E
Biochemistry. 1979 Mar 6;18(5):882-9. doi: 10.1021/bi00572a023.
Conformational properties of native, denatured, and renatured ovotransferrin were studied. The samples were denatured either in 7.2 M urea or in acidic (pH 3.0) conditions for periods up to a few hours. Combined data from quasielastic light scattering and transient electric birefringence were used to estimate the molecular dimensions under the various conditions. The native ovotransferrin is best described as a prolate ellipsoid with a major axis a = 68 A and a minor axis b = 21 A. Such an ellipsoidal shape is consistent with a globular particle where the solvation factor is approximately 0.28 mg/mg of solute. The urea-denatured sample was more expanded and more globular than the native sample. This observation was supported by a decrease in helical content, which was shown using circular dichroism data. Complete recovery of conformation and capacity to form a colored complex with Fe3+ seemed to occur with the simple dilution of urea or by adjustment of the low pH sample to pH 7.3.
研究了天然、变性和复性卵转铁蛋白的构象性质。样品在7.2 M尿素中或在酸性（pH 3.0）条件下变性长达数小时。结合准弹性光散射和瞬态电双折射的数据用于估计各种条件下的分子尺寸。天然卵转铁蛋白最好描述为一个长轴a = 68 Å和短轴b = 21 Å的长椭球体。这种椭球形状与一个溶剂化因子约为0.28 mg/mg溶质的球状颗粒一致。尿素变性样品比天然样品更膨胀且更呈球状。使用圆二色性数据显示的螺旋含量降低支持了这一观察结果。通过简单稀释尿素或将低pH样品调节至pH 7.3，似乎发生了构象的完全恢复以及与Fe3+形成有色络合物的能力。
