摘要
利用荧光光谱(FS)、紫外吸收光谱(UV)、圆二色谱(CD)和共振光散射谱(RLS)研究熊果酸(UA)与牛血清白蛋白(BSA)相互作用.荧光光谱显示,熊果酸能与BSA分子相结合,结合位点数为0.912 4,结合常数为0.693 4×103 L.mol-1,能量转移效率为0.036,结合距离为1.43nm,并导致BSA荧光产生静态淬灭,其淬灭主要由色氨酸所贡献,并随熊果酸的浓度增高相应淬灭作用增强;紫外和圆二色光谱显示,熊果酸对BSA的紫外吸收峰具有增色效应,并减少BSA中α-螺旋含量,由56.72%减少至39.08%,使BSA的二级结构发生显著变化;共振光散射光谱显示,熊果酸使BSA分子聚集形成分子聚集体.
Fluorescence spectroscopy（FS）,circular dichroism（CD）,ultraviolet（UV）,resonant light scattering（RLS） spectroscopy are used to study the interaction between bovine serum albumin（BSA） and ursolic acid（UA）.FS results show that ursolic acid reduce the fluorescence intensity of bovine serum albumin.The way of fluorescence quenching is static quenching.And the binding sites n=0.912 4,the binding constant K=0.693 4×103 L·mol-1,energy-transfer efficiency 0.036,the binding distance 1.43 nm,but also result in static fluorescence quenching,which is contributed by tryptophan and enhanced with the increase of ursolic acid concentration.UV and CD results indicat that ursolic acid has hyperchromic effect on BSA and reduces α-helix in BSA from 56.72% to 39.08% that significantly changes its secondary structure.Resonant light scattering results show that resonant light scattering makes BSA molecular aggregate.
出处
《西北师范大学学报（自然科学版）》
CAS
北大核心
2013年第1期78-85,95,共9页
Journal of Northwest Normal University(Natural Science)
基金
国家自然科学基金资助项目(30960464)
西北师范大学知识与科技创新工程资助项目(NWNU-KJCXGC-03-65)
关键词
熊果酸
牛血清白蛋白
荧光光谱
圆二色光谱
共振光散射
ursolic acid
bovine serum albumin
fluorescence spectroscopy
circular dichroism
resonant light scattering
