结核杆菌小分子热休克蛋白Hsp16.3的高效自发再折叠和再组装

The High-efficient Spontaneous Refolding and Reassembly of Mycobacterium tuberculosis Small Heat Shock Protein Hsp16.3

来自结核杆菌的小分子热休克蛋白Hsp16 3以九聚体的形式存在 .用三种不同的强变性条件 (10 0℃加热15min ,12mol/L脲或 8mol/L盐酸胍处理 4h)将Hsp16 3变性 ,然后通过冷却或透析使之复性 ,并利用孔径梯度聚丙烯酰胺凝胶电泳和圆二色性光谱比较了变性 复性前后Hsp16 3的各个层次高级结构 .结果显示 ,变性的Hsp16 3几乎可以完全恢复至天然构象 ,这表明小分子热休克蛋白Hsp16 3具有很强的自发折叠和组装能力 .

The small heat shock protein Hsp16.3 of Mycobacterium tuberculosis was shown to be a trimer-of-trimers. Hsp16.3 proteins were denatured under three kinds of strong denaturing conditions by heat treatment (at 100degreesC, 15 min) or chemical reagents (12 mol/L urea or 8 mol/L guaridine, 4 hours) and then were renatured by cooling or dialysis. The secondary, tertiary and quaternary structures of Hsp16.3 were investigated by using far, and near- UV circular dichroism as well as pore-gradient polyacrylamide gel electrophoresis, respectively. The data clearly showed that the renatured Hsp16.3 proteins almost completely regained its native conformation, thus suggesting the strong ability of Hsp16.3 to refold and reassembly to its native conformation.