超声和高压处理对牛血清白蛋白结构的影响

The BSA Structure Disruption by Ultrasound and High Pressure Treatment

目的研究牛血清白蛋白经过超声和高压处理前后的结构变化,以及自由基清除剂对其结构变化的影响。为进一步研究细胞破碎和乳化蛋白时超声和高压处理对蛋白的影响提供参考。方法将BSA溶液经过超声和高压处理,然后利用高效液相色谱(HPLC)、动态光散射(DLS)、非变性聚丙烯酰胺凝胶电泳(nondenaturing SDS-PAGE)以及园二色谱(CD)等手段检测处理前后的结构变化。结果发现超声使BSA严重聚集,加入自由基清除剂可以减少聚集的产生。而高压处理后的BSA未出现聚集,但二级结构发生了变化。结论超声和高压这两种处理方法对蛋白损伤机理不同,所以选择合适的破碎方法要根据蛋白自身的性质而定。

To investigate the structure disruption of BSA （1mg/ml, dissolved in PBS ） induced by ultrasonication and the French press. The BSA solution was passed through the French press and received ultrasound irradiation, and then detected by HPLC （High-performance liquid chromatography）, DIS （Dynamic Light Scattering）, CD（ Circular Dichroism）and nondenaturing SDS-PAGE. Detection results showed that BSA was polymerized after ultrasound irradiation and the polymerization can be reduced by adding mannitol （free radical scavenger）. This means that the free radical play an important role in this process. However, the BSA passing through the French press for several times wasn＇t polymerized, and the secondary structure was somewhat destroyed. These results suggested that ultrasound irradiation and French press destroy the molecular structure in different manners, so that the suitable cell lyses methods should be selected according to the characteristics of the protein.