摘要
研究了Hg2+在生物体内与牛血清白蛋白相互作用的毒性机理以及蛋白质的微观结构变化。测定了Hg2+与牛血清白蛋白(BSA)复合体系的红外光谱(FT-IR)和圆二色谱(CD),并对图谱进行拟合解析处理。红外光谱实验数据表明Hg2+与BSA发生作用的结合位点可能包括—SH、—OH和—NH基团,采用红外拟合技术对BSA二级结构的变化进行了研究,结果表明蛋白质α-螺旋结构含量降低,β-折叠结构含量升高。圆二色谱图也表明由于一定浓度的Hg2+与BSA结合,从而导致蛋白质的二级结构被破坏,这与拟合红外光谱得到的蛋白质二级结构数据相吻合。Hg2+与牛血清蛋白作用致使蛋白质的构象改变,形成金属离子与蛋白质作用的复合物,因而蛋白质失去活性导致生物体发生病变。
The toxicity mechanism of Hg^2＋ for organisms and the change of protein microstructure for the interaction between heavy metal ions and proteins were investigated by Fourier transform infrared （FF- IR） spectrometer and circular dichroism（CD） spectrometer. The change of secondary structure of bovine serum albumin（BSA） were analyzed by IR spectral curve-fitting, and the percentage of secondary structure of BSA, including α-helix,β-sheet, β-turn and random, were calculated. The results form IR spectra indicated that BSA could react with Hg^2＋ by providing multiple binding sites, such as --NH, --SH and --OH groups. The curve fitting of IR spectra also indicated that the content of α-helix decreases while that of β-sheet increases, which is consistent with the results obtained from CD spectra. Therefore, the interaction of Hg^2＋ and BSA could lead to the change of BSA secondary structure from α-helix to β-sheet and the lost of its bio-activity, finally producing pathological change in organism.
出处
《分析测试学报》
CAS
CSCD
北大核心
2009年第4期462-465,共4页
Journal of Instrumental Analysis
基金
平顶山学院高层次人才基金资助项目(2007025)
