Schwab F J, Appel H, Neu M, Thies W G
Institut für Experimentelle Kernphysik, Universität Karlsruhe, Federal Republic of Germany.
Eur Biophys J. 1992;21(2):147-54. doi: 10.1007/BF00185429.
Using the perturbed angular correlations (PAC) technique, the formation of hafnium-ovotransferrin complexes has been studied. Two binding configurations at each of the two specific binding-sites of the protein have been observed. They are characterized by well-defined electric quadrupole frequencies. Information about the dynamics of the protein was derived from temperature dependent measurements of the relaxation constant. The well-resolved spectra taken with fast BaF2-detectors allow a precise determination of the relaxation behaviour of the protein. The results are compared with the predictions from a hydrodynamic model for the reorientation of macromolecules. Thus the hydrodynamic volume of ovotransferrin and its N-terminal half-molecule were determined. The ovotransferrin volume is in agreement with a value derived for human serum transferrin from small angle neutron scattering. From experiments with immobilized protein material there is evidence for internal protein dynamics which is probed by the Hf-ion bound to the specific metal-sites.
利用扰动角关联（PAC）技术，对铪 - 卵转铁蛋白复合物的形成进行了研究。在蛋白质的两个特异性结合位点处均观察到了两种结合构型。它们的特征在于明确的电四极频率。关于蛋白质动力学的信息来自于对弛豫常数的温度依赖性测量。使用快速BaF₂探测器获得的分辨率良好的光谱能够精确测定蛋白质的弛豫行为。将结果与大分子重定向的流体动力学模型的预测进行了比较。由此确定了卵转铁蛋白及其N端半分子的流体动力学体积。卵转铁蛋白的体积与从小角中子散射得出的人血清转铁蛋白的值一致。从固定化蛋白质材料的实验中可以证明存在内部蛋白质动力学，这是由结合到特定金属位点的Hf离子探测到的。
