利用光子相关光谱研究蛋白分子相互作用

Experimental Study of Protein Interactions by Photon Correlation Spectrum

利用光子相关光谱技术研究了人血清白蛋白分子在不同蛋白浓度和pH值条件下的扩散系数。结果表明库仑力对蛋白质的扩散起主要作用,在等电位点下(pH=5.2)库仑力的影响消失,蛋白质的扩散系数最小;等电点测量出扩散系数随浓度的增加而线性减小,主要原因是蛋白质间的库仑排斥力变小,引力得到相对增强,测得人血清白蛋白的半径为3.44±0.01nm。

The diffusion coefficient of HSA (human serum albumin) was measured by photon correlation spectrum in different concentrations and pH. The results indicate that coulomb interaction between the charged proteins is the main contribution to the diffusion coefficient. At the isoelectric point(5. 2) ,the effect of coulomb vanishes, the diffusion coefficient of protein closes to minimal,and linearly decreases with the increase of concentration. The main reason is that the coulomb interactions between proteins decrease,and the attractive potential increases relatively. The diameter of HSA is obtained as 3. 44±0.01nm.