温度、酸碱度和盐离子浓度对curcin紫外光谱和荧光光谱的影响

Effect of Temperatures,pH Value and Salt Concentration on Curcin's UV and Fluorescence Spectra

将麻疯树核糖体失活蛋白curcin在不同温度、酸碱度和Na Cl浓度下进行孵育,测定其紫外光谱和荧光光谱的变化,对影响其结构稳定性的因素进行初步探究。研究结果显示,curcin对温度和p H变化相对敏感。当温度上升到70℃后,紫外吸收明显增加,在348nm时新增一个明显的荧光激发峰。极端p H值对curcin结构影响同样较大,特别是当p H值为11时,在348nm处新增荧光激发峰。上述现象表明,温度和酸碱度的改变可能导致curcin中含色氨酸的疏水核心结构出现暴露在外的变性过程。Curcin对上述两个因素的敏感性提示其稳定性还有待提高,才能满足蛋白质药物开发的需求。

After incubated at different temperatures, pH and NaCI concentration, the UV and fluorescence spectra of curcin were measured respectively. The results showed that eurcin was relatively more sensitive to temperatures and pH values than to ionic strength. It was found that when the temperature reaching to 70℃, its ultraviolet absorption significantly increased, meantime a new excitation peak appeared at 348nm. Similarly, extreme pH （pill 1 ） also resulted a new excitation peak at 348nm. It suggested that a tryptophan- containing hydrophobic core inside the curcin might moved to the outside and hydrophilic environment. The sensitivity of curcin to high temperature and extreme pH also stated that there was lots of work on modification of curcin structural stability before its medical application.