Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Shandong Province, 27# Shanda South Road, Jinan, 250100, People's Republic of China.
J Fluoresc. 2012 Jan;22(1):239-45. doi: 10.1007/s10895-011-0950-z. Epub 2011 Aug 27.
The effect of Pb(2+) targeted to bovine serum albumin (BSA) in vitro was investigated by fluorescence, synchronous fluorescence, UV absorption and circular dichroism (CD) spectrophotometry. The characteristic fluorescence of BSA was quenched, which indicated that Pb(2+) changed the skeleton of BSA and caused the gradual exposure of aromatic amino acid residues (Trp, Tyr, Phe) in the internal hydrophobic region of BSA. When the concentration of Pb(2+) was higher than 1 × 10(-4) mol/L, the BSA was completely denatured. The excess lead ion interacted with the aromatic amino acid residues of BSA exposed to the solution, which decreased the fluorescence of BSA further. According to the experiment results, we found that a lead-BSA complex was formed following static quenching and the binding site was calculated approximately equal to 1. This work reflected the interaction mechanism of BSA and Pb(2+) from the perspective of spectroscopy.
采用荧光光谱法、同步荧光光谱法、紫外吸收光谱法和圆二色光谱法（CD）研究了 Pb(2+)与牛血清白蛋白（BSA）体外相互作用的影响。BSA 的特征荧光被猝灭，表明 Pb(2+)改变了 BSA 的骨架，导致 BSA 内部疏水区的芳香族氨基酸残基（色氨酸、酪氨酸、苯丙氨酸）逐渐暴露。当 Pb(2+)浓度高于 1×10(-4)mol/L 时，BSA 完全变性。多余的铅离子与溶液中暴露的 BSA 的芳香族氨基酸残基相互作用，进一步降低了 BSA 的荧光。根据实验结果，我们发现形成了 Pb-BSA 复合物，这是一种静态猝灭，并且计算出的结合位点约等于 1。这项工作从光谱学的角度反映了 BSA 和 Pb(2+)之间的相互作用机制。
