School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Shandong Province, 27# Shanda South Road, Jinan 250100, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2013 May;108:50-4. doi: 10.1016/j.saa.2013.01.072. Epub 2013 Feb 8.
The toxicity of hydroxyl group of isopropanol to trypsin in aqueous solution was investigated by techniques including UV-visible absorption spectroscopy, fluorescence spectroscopy, circular dichroism (CD) spectroscopy, enzyme activity assay and molecular docking technology. The results of UV-visible absorption spectroscopy and CD spectra indicate that isopropanol could change the secondary structure of trypsin by increasing the content of α-helix and decreasing the content of β-sheet. The tertiary structure of trypsin was also changed owing to the loss of environmental asymmetry of amino acid residues. Isopropanol bound into a hydrophobic cavity on the surface of trypsin by a hydrogen bond located between the hydrogen atom on the hydroxyl of isopropanol and the oxygen atoms on SER 214 and hydrophobic interaction, as the molecular docking results showed. In addition, isopropanol could affect the function of trypsin by increasing its catalytic activity.
采用紫外可见吸收光谱法、荧光光谱法、圆二色光谱法、酶活性测定法和分子对接技术研究了异丙醇羟基对水溶液中胰蛋白酶的毒性。紫外可见吸收光谱和圆二色光谱的结果表明，异丙醇通过增加α-螺旋含量和减少β-折叠含量来改变胰蛋白酶的二级结构。由于氨基酸残基环境不对称性的丧失，胰蛋白酶的三级结构也发生了变化。分子对接结果表明，异丙醇通过氢键将其羟基上的氢原子与 SER 214 上的氧原子结合，并通过疏水相互作用结合到胰蛋白酶表面的疏水腔内。此外，异丙醇还可以通过增加其催化活性来影响胰蛋白酶的功能。
