Bian W, Sun S, Wong R N, Zhou Q, Hu X
Department of Chemistry, Tsinghua University, 100084 Beijing.
Guang Pu Xue Yu Guang Pu Fen Xi. 2000 Aug;20(4):471-3.
Fourier-transform infared spectroscopy, combined with resolution-enhancement techniques including second-derivative spectroscopy, Fourier self-deconvolution and curvefitting technique, was used to investigate the thermally induced unfolding process of anti-HIV-I toxin protein trichosanthin. During heating from 25 degrees C to 85 degrees C, the peak of Amide I shifted to 1618 cm-1 while the secondary structural contents change with the temperature. Upon cooling the protein from 85 degrees C to 25 degrees C, the contour of the Amide I do not change. All these show that the thermal unfolding of trichosanthin is an irreversible intermolecular aggregation process between 25 degrees C and 85 degrees C. The changes of secondary structures with temperature suggest the presence of folding intermediates.
傅里叶变换红外光谱结合包括二阶导数光谱、傅里叶自去卷积和曲线拟合技术在内的分辨率增强技术，用于研究抗HIV-I毒素蛋白天花粉蛋白的热诱导解折叠过程。在从25℃加热到85℃的过程中，酰胺I的峰移至1618 cm-1，同时二级结构含量随温度变化。当蛋白质从85℃冷却到25℃时，酰胺I的轮廓不变。所有这些表明，天花粉蛋白在25℃至85℃之间的热解折叠是一个不可逆的分子间聚集过程。二级结构随温度的变化表明存在折叠中间体。
