Study on the Interaction Between Bovine Serum Albumin and Potassium Perfluoro Octane Sulfonate

The interactions between potassium perfluorooctanesulfonate (PFOS) and bovine serum albumin (BSA) were studied by fluorescence spectroscopy. The association constants between PFOS and BSA were obtained by fluorescence enhancing and fluorescence quenching respectively. Furthermore, fluorescence quenching was studied at different temperatures, and the binding constant was also determined by the method of fluorescence quenching. According to the thermodynamic parameters, the main binding force could be judged. The experimental results revealed that BSA and PFOS had strong interactions. The mechanism of quenching belonged to dynamic quenching and the main sort of binding force was hydrophobic force. IR-spectra proved the interaction changed the conformation of BSA.     

灯盏花素与牛血清白蛋白相互作用的荧光光谱研究

采用荧光光谱法和紫外吸收光谱法研究了灯盏花素(BR)与牛血清白蛋白(BSA)的相互作用;利用热力学方程计算了295K和308K下的热力学参数ΔH、ΔG和ΔS,根据Stern-Volmer方程求出了猝灭常数和结合常数.结果表明,BR对BSA的荧光具有猝灭作用,其猝灭机制为动态-静态联合猝灭,BSA发射峰略有蓝移.BR与BSA之间的作用力主要为疏水作用.     

Investigation of the Interaction between Nitrite Ion and Bovine Serum Albumin Using Spectroscopic and Molecular Docking Techniques

The interaction between nitrite ion and bovine serum albumin (BSA), in an aqueous environment, was studied using spectroscopic methods, including fluorescence quenching technique, synchronous fluorescence, UV? Vis spectrophotometry and Resonance Rayleigh Scattering (RRS), and molecular docking technique. The experimental results showed that nitrite ion effectively quenched the intrinsic fluorescence of BSA with the static quenching. The ion‐BSA binding constant was determined to be 3.69×10³ L mol^?1. As the results showed the stoichiometry of binding nitrite ion to BSA was 1 : 1. Furthermore the thermodynamic parameters and nature of the binding force were calculated. The negative ΔH^o and ΔS^o values of reaction between nitrite ion and BSA indicated the predominant forces in the ion‐BSA interactions are hydrogen bonding interactions. Based on the Förster’s theory of non‐radiative energy transfer, the binding distance between nitrite ion and the inner tyrosine and tryptophan residue of BSA were determined to be 2.16 nm. Furthermore binding site of this ion on BSA was carried out by molecular docking technique.     

锌(Ⅱ)存在下灯盏花素与BSA相互作用的光谱分析

运用荧光光谱、吸收光谱研究了灯盏花素(Breviscapinun,BR)与牛血清白蛋白(Bovine Serum Albumin,BSA)的相互作用.BR对BSA的荧光光谱具有猝灭作用,其猝灭机制为静态-动态联合猝灭,BSA发射峰蓝移.Zn2+的存在使得BSA发射峰蓝移程度降低,猝灭常数、结合常数、结合位点数减小.在较大浓度Zn2+存在下,BR与BSA作用的相关系数增大,猝灭机制变为静态猝灭.从Zn2+与BR的竞争作用,热力学参数的变化、配位化合物的形成3个方面分析了影响BR与BSA作用的因素.     

酮咯酸、菲普拉宗与血清蛋白相互作用的研究

血清蛋白是血浆中含量最丰富的重要载体蛋白,它可与许多内源性物质和药物广泛结合［１］,酮咯酸、菲普拉宗分别为非甾类、吡唑酮类消炎镇痛新药［２］．有关酮咯酸、菲普拉宗与蛋白质相互作用的文献尚未见报道．本文研究了在人体生理条件下,酮咯酸、菲普拉宗与牛血清蛋白、人血清蛋白的相互作用,利用药物对血清蛋白荧光的猝灭求出了酮咯酸、菲普拉宗与蛋白质的结合常数和结合位置．并根据热力学参数确定了它们之间的主要作用力类型．这对于阐明不同药物对蛋白的不同作用方式及药物在人体内的作用机制都有一定的意义．１　实验部分１．１…     

金属离子对次野鸢尾黄素与牛血清白蛋白相互作用的影响

应用荧光光度法研究了金属离子Fe3 、Ca2 、Cu2 或Mn2 对次野鸢尾黄素(IFR)与牛血清白蛋白(BSA)相互作用的影响.实验结果表明,不存在金属离子时,IFR对BSA的荧光猝灭过程为动态猝灭,其结合过程的表观结合常数KA值为104～105数量级,结合位点数n约等于1.由热力学参数得出IFR与BSA结合过程是一个熵增加、Gibbs自由能降低的自发过程,分子间相互作用力以疏水作用力为主.在Fe3 或Ca2 抖的存在下,IFR对BSA的荧光猝灭类型由动态猝灭转变为静态猝灭,作用力类型也由以疏水作用力为主转变为以氢键与范德华力为主或以静电引力为主.Cu2 或Mn3 存在下,IFR对BSA的荧光猝灭类型及分子间作用力类型均没有发生改变.四种金属离子的参与都使得IFR与BSA结合作用的袁观结合常数发生了明显的变化,但结合位点数仍维持在1左右.     

Interaction Between Fluorinated Amphiphilic Copolymer P(HFMA)-g-P(SPEG) and BSA

A novel fluorinated amphiphilic copolymer P(HFMA)-g-P(SPEG) was synthesized. The interactions between P(HFMA)-g-P(SPEG) and bovine serum albumin (BSA) were studied by synchronous fluorescence and intrinsic fluorescence spectroscopy. It was concluded through synchronous fluorescence that P(HFMA)-g-P(SPEG) mainly bound to tryptophan residues of BSA. Intrinsic fluorescence results revealed that BSA and P(HFMA)-g-P(SPEG) had strong interactions. The mechanism of quenching belonged to dynamic quenching and the main sort of binding force was hydrophobic force. The hydrophobic interaction between P(HFMA)-g-P(SPEG) and BSA was conformed by micropolarity and TEM photographs.     

三价铁对灯盏花素与牛血清白蛋白相互作用的影响

运用荧光光谱、紫外吸收光谱探讨了Fe3+对灯盏花素(BR)与牛血清白蛋白(BSA)相互作用的影响;从Fe3+与BSA的静电作用、配位结合以及Fe3+与BR的配位作用等方面分析了影响BR与BSA相互作用的因素.结果表明,Fe3+不改变BSA与BR的作用机制,但使得二者结合的猝灭常数、结合常数及结合位点数减小.     

葛根素及其衍生物与牛血清白蛋白相互作用研究

采用改造后的Atherton-Todd反应合成了葛根素的两种磷酰化异黄酮, 并应用荧光光谱法研究了葛根素及其磷酰化产物与牛血清白蛋白(BSA)的相互作用. 结果显示葛根素及其磷酰化产物均能与BSA发生相互作用, 但磷酰化产物与蛋白的结合作用相对较弱; 三个小分子对BSA荧光的猝灭是静态猝灭过程, 结合力以疏水作用力为主; 依据能量转移原理求得小分子与BSA间结合距离均小于7 nm. 通过比较葛根素及其磷酰化产物与BSA的相互作用, 初步探讨了三个小分子分子结构与其结合能力之间的联系, 并进一步考察了金属离子对结合反应的影响.     

光谱法与分子模拟技术研究丽春红2R与牛血清蛋白的相互作用

采用荧光光谱、同步荧光光谱、紫外-可见吸收光谱及分子模拟技术研究了模拟生理条件下丽春红2R(P2R)与牛血清白蛋白(BSA)的相互作用。实验结果表明,P2R-BSA体系的荧光猝灭机制为内源荧光猝灭,猝灭原因为静态猝灭和非辐射能量转移;计算了不同温度下体系的结合常数Ka及结合位点数n;根据热力学参数推断出作用力类型;求出室温下荧光给体-受体间的结合距离;同步荧光法证实丽春红2R对BSA构象未产生影响;分子模拟研究结果表明二者间的主要作用力为氢键和疏水作用力。     

Characterization of the interaction between farrerol and bovine serum albumin by fluorescence and circular dichroism

The binding of farrerol to bovine serum albumin (BSA) in aqueous solution was investigated by fluorescence quenching spectra, synchronous fluorescence spectra, circular dichroism (CD) and the three-dimensional (3D) fluorescence spectra at pH 7.40. The results of fluorescence titration indicated that farrerol could quench the intrinsic fluorescence of BSA in a static quenching way. The cause of showing upward curvy patterns in Stern-Volmer plots was analyzed. The binding sites number n and binding constant K using fluorescence quenching equation at 310 K were calculated. The binding distance and the energy transfer efficiency between farrerol and BSA were also obtained according to the theory of F?rster's non-radiation energy transfer. The effect of some metal ions on the binding constant of farrerol with BSA was also studied. The effect of farrerol on the conformation of BSA was analyzed using CD, synchronous fluorescence spectra and three-dimensional (3D) fluorescence spectra under experimental conditions. Furthermore, the fluorescence displacement experiments indicated that farrerol could bind to the site I of BSA.     

可可碱与牛血清白蛋白作用光谱特性的研究

本文应用荧光光谱法研究了可可碱（TB）与牛血清白蛋白（BSA）相互作用的光谱特性。测定了18℃、30℃、40℃温度下的结合常数KA分别为1．68×10^4、1．58×10^4、1．45×10^4L／mol,结合位点数咒分别为1．04、1．03、1．03。实验结果表明：TB对BSA内源荧光的猝灭机理主要为静态猝灭;热力学参数探讨其相互作用机理,TB主要以静电力与BSA相互作用;研究了TB对BSA构象的影响,BSA的荧光主要源于色氨酸残基。同时研究了Cu^2＋存在下TB与BSA的相互作用。     

伊文思蓝作荧光探针研究牛血清白蛋白与氨苄青霉素之间的竞争反应

用伊文思蓝(Evans blue, EB)作荧光探针研究了氨苄青霉素(Ampicillin, A)对牛血清白蛋白(Bovine serum albumin, BSA)的竞争反应. 伊文思蓝与牛血清白蛋白作用, 使牛血清白蛋白荧光发生猝灭, 根据Stern-Volmer方程及荧光寿命研究了荧光猝灭的类型及机理. 结果表明, 猝灭类型为静态猝灭, 即伊文思蓝和牛血清白蛋白形成了一种稳定的复合物. 伊文思蓝与牛血清白蛋白的结合常数KBSA-EB=1.122×106 L/mol, 结合点数n=0.9935, 并确定了EB和BSA之间的热力学常数及作用力类型. 当加入氨苄青霉素后, 牛血清白蛋白的相对荧光强度恢复. 这表明氨苄青霉素与伊文思蓝对牛血清白蛋白发生了竞争反应. 探讨了该竞争反应的相关机理, 求出了伊文思蓝与氨苄青霉素的结合常数为KEB-A=7.131×105 L/mol.     

二价铅离子与牛血清白蛋白相互作用的荧光光谱研究

用荧光法研究了二价铅离子与牛血清白蛋白的相互作用,测定了不同条件下pb2+与BSA作用的荧光光谱,并通过热力学计算探讨了二者的作用方式、BSA荧光的猝灭机理、Pb2+与BSA之间的结合常数及结合位点.结果表明,Pb2+对BSA的荧光猝灭属于静态猝灭,pb2+通过疏水作用力进入BSA的疏水腔与之发生相互作用,反应的△G=...     

几种金属离子对胭脂红与牛血清白蛋白相互作用的影响——荧光光谱研究

利用荧光光谱法研究了不同温度(15、27、39℃)下食用合成色素胭脂红对牛血清白蛋白(BSA)的内源荧光猝灭特性,考察了Cu2+、Ni 2+、Pb2+等金属离子对二者相互作用的影响,并测定了不同温度下的猝灭常数KSV、结合常数KA和结合位点数n.结果表明,3种金属离子基本不影响胭脂红对BSA荧光猝灭机理,但Cu2+、Ni 2+、Pb2+离子都与BSA有一定的结合能力,可在不同程度上增强胭脂红与BSA的结合作用及其对BSA内源荧光的猝灭.     

光谱法研究牡荆素与蛋白质相互作用及共存金属离子的影响

利用荧光光谱法和紫外-可见光谱法研究了牡荆素(VT)与牛血清白蛋白(BSA)之间的相互作用.VT对BSA的荧光猝灭为动态猝灭过程,测定了不同温度下的猝灭常数;根据F(o)rster非辐射能量转移理论,计算出VT在BSA中的结合位置与色氨酸残基间的距离为2.675.nm;通过热力学参数推断出VT与BSA之间主要靠疏水作用...     

变色酸与牛血清白蛋白的相互作用

采用荧光光谱法和紫外-可见分光光度法研究了变色酸与牛血清白蛋白之间的相互作用。结果表明:变色酸对牛血清白蛋白有较强的荧光猝灭作用。根据Stern-Volmer方程得到了荧光猝灭常数,并判断由于与变色酸反应而导致牛血清白蛋白的荧光猝灭属于静态猝灭。采用Lang-muir单分子吸附模型计算了结合常数和结合位点数。从计算得到的热力学参数ΔH和ΔS推断了变色酸与血清白蛋白反应的作用力为氢键和范德华力。     

激光光散射与荧光光谱法研究大豆苷与牛血清白蛋白作用及聚集态

荧光光谱法和动态光散射法研究大豆苷与牛血清白蛋白在生理条件下的相互作用. 研究表明, 大豆苷与牛血清白蛋白能形成2∶l复合物, 荧光猝灭属于静态猝灭过程; 大豆苷与牛血清白蛋白分子间主要的结合作用力为疏水作用; 310 K下, 两者结合常数和结合位点数分别为7.4×l04 L•mol―1和1.75; 大豆苷使牛血清白蛋白的构象发生了变化; 动态光散射数据探讨了牛血清白蛋白与大豆苷分子产生聚集与之相互作用, 进一步证实了牛血清白蛋白在大豆苷水溶液中的构象变化. 实验结果为进一步研究大豆苷对心血管疾病的药理作用, 特别是对血浆蛋白构象的影响提供了重要依据.     

白杨素磺酸盐与牛血清白蛋白的相互作用

合成了白杨素磺酸钠和白杨素磺酸钙两种白杨素磺酸盐衍生物,并分别采用荧光光谱法研究了它们与牛血清白蛋白(BSA)的相互作用。结果表明:两种白杨素磺酸盐对BSA有较强的荧光猝灭作用,根据Stern-Volmer方程得到的荧光猝灭常数,可判断由于与白杨素磺酸盐反应而导致BSA的荧光猝灭均属于静态猝灭。采用位点结合模型公式和Frster非辐射能量转移理论计算了结合常数、结合位点数、结合距离。从计算得到的热力学参数焓变ΔH和熵变ΔS,推断了白杨素磺酸钠与BSA之间的作用力为静电引力,而白杨素磺酸钙与BSA之间的作用力为氢键和范德华力。并应用同步荧光技术研究了白杨素磺酸盐对BSA构象的影响。     

Study of the interaction of carbamazepine with bovine serum albumin by fluorescence quenching method.

The interaction between carbamazepine (CBZ) and bovine serum albumin (BSA) was studied using fluorescence spectroscopy (FS) and ultraviolet spectroscopy (UV). The experimental results showed that the CBZ could insert into the BSA and quench the inner fluorescence of BSA by forming the CBZ-BSA complex. It was found that both static quenching and non-radiation energy transfer were the main reasons leading to the fluorescence quenching. The apparent binding constants (K) between CBZ and BSA were found to be 1.8 x 10(4) (27 degrees C) and 2.8 x 10(4) (37 degrees C) and the binding site values (n) were 0.97 (27 degrees C) and 1.01 (37 degrees C), respectively. According to the Forster theory of non-radiation energy transfer, the binding distances (r) between CBZ and BSA were 3.6 nm and 3.4 nm at 27 degrees C and 37 degrees C, respectively. The process of the binding was a spontaneous molecular interaction in which entropy increased and Gibbs free energy decreased, indicating that the interaction between CBZ and BSA was mainly driven by the hydrophobic force.