A. N. Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky Prosp. 33, 119071 Moscow, Russia.
Biophys Chem. 2009 Dec;145(2-3):79-85. doi: 10.1016/j.bpc.2009.09.003. Epub 2009 Sep 12.
We applied different methods (differential scanning calorimetry, circular dichroism, Fourier transform infrared spectroscopy, and intrinsic fluorescence) to investigate the thermal-induced changes in the structure of small heat shock protein Hsp22. It has been shown that this protein undergoes thermal-induced unfolding that occurs within a very broad temperature range (from 27 degrees C to 80 degrees C and above), and this is accompanied by complete disappearance of alpha-helices, significant decrease in beta-sheets content, and by pronounced changes in the intrinsic fluorescence. The results confirm predictions that Hsp22 belongs to the family of intrinsically disordered proteins (IDP) with certain parts of its molecule (presumably, in the alpha-crystallin domain) retaining folded structure and undergoing reversible thermal unfolding. The results are also discussed in terms of downhill folding scenario.
我们应用了不同的方法（差示扫描量热法、圆二色性、傅里叶变换红外光谱和内荧光）来研究小热休克蛋白 Hsp22 的热诱导结构变化。结果表明，该蛋白经历了热诱导解折叠，发生在非常宽的温度范围内（27°C 至 80°C 及以上），这伴随着α-螺旋的完全消失，β-折叠含量显著降低，以及内荧光的明显变化。结果证实了 Hsp22 属于无规卷曲蛋白 (IDP) 家族的预测，其分子的某些部分（推测在α-晶状体域）保留折叠结构，并经历可逆的热诱导解折叠。结果还根据下坡折叠情景进行了讨论。
