共查询到20条相似文献,搜索用时 312 毫秒
1.
《理化检验(化学分册)》2010,(11)
采用荧光光谱法研究丹参酮Ⅰ(TSNⅠ)与人血清白蛋白(HSA)结合反应的特征。试验发现:丹参酮Ⅰ对人血清白蛋白有较强的荧光猝灭作用。根据由Stern-Vol mer方程和Lineweaver-Burk双倒数方程得到的荧光猝灭常数,判断由于与丹参酮Ⅰ反应而导致人血清白蛋白的荧光猝灭属静态猝灭。并从所计算得到的热力学参数ΔH和ΔS,推断人血清白蛋白与丹参酮Ⅰ反应的结合力为静电力。根据同步荧光光谱研究的结果表明:人血清白蛋白的构象不因与丹参酮Ⅰ反应而改变。 相似文献
2.
3.
运用荧光光谱、紫外光谱和计算机模拟分子对接等技术,研究了在模拟生理条件下还原型辅酶烟酰胺腺嘌呤二核苷酸(NADH)与人血清白蛋白(HSA)的作用方式及热力学特征。结果表明,NADH与人血清白蛋白的荧光猝灭机理属于静态猝灭;NADH与HSA在温度283K和310K时的结合常数和结合位点数分别为1.972×104 L.mol-1、0.9657和1.468×104 L.mol-1、0.9105,通过热力学计算得到反应的热力学参数;同步荧光光谱表明NADH使色氨酸残基的微环境亲水性增强;分子模型研究表明,二者通过疏水力、静电力和氢键共同作用结合。 相似文献
4.
5.
合成了2-(4-甲基苯基)-3-(N-乙酰基)-5-(2-羟基苯基)-1,3,4-噁唑啉(MPAHO),并用核磁共振波谱法和红外光谱法对其进行了表征。采用荧光光谱技术研究了MPAHO与人血清白蛋白(HSA)的相互作用。结果表明:MPAHO对HSA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MPAHO反应而导致HSA的荧光猝灭均属于静态猝灭。采用位点结合模型公式和Frster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MPAHO与HSA之间的作用力为静电引力。并应用同步荧光光谱和三维荧光技术研究了MPAHO对HSA构象的影响。 相似文献
6.
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。 相似文献
7.
用荧光、紫外光谱、分子对接研究了柚皮苷与人血清白蛋白(HSA)在pH=7.40的Tris-HCl缓冲溶液中相互作用的情况。结果表明,柚皮苷对人血清白蛋白的内源荧光有明显的猝灭作用,猝灭过程为动态猝灭。根据Stern-Volmer方程计算得到柚皮苷与HSA在293、298和310 K下的结合常数分别为2.472×105、2.210×105和1.392×104L·mol-1,结合位点数约为1。由实验计算出热力学参数焓变ΔH为-16.8 kJ·mol-1,ΔS为46.0 J·mol-1·K-1,推断出柚皮苷与人血清白蛋白之间主要靠疏水作用和静电引力结合,与分子模拟的结果相同。同时采用同步荧光技术考察了柚皮苷对HSA构象的影响。 相似文献
8.
9.
10.
在模拟生理条件下,采用荧光光谱法、三维荧光光谱法、圆二色谱法以及分子对接模拟法,研究了二水土霉素与牛血清白蛋白(BSA)之间的相互作用。荧光光谱表明,二水土霉素能有效猝灭BSA的内源荧光,猝灭机制属静态猝灭。根据Vant’s Hoff方程确定结合过程中的热力学参数ΔS、ΔH,表明两者之间作用为疏水作用力。根据Foster’s非辐射能量转移理论,计算得到结合距离r=2.56nm。同步荧光光谱、三维荧光光谱、圆二色谱结果证明盐酸四环素能够改变BSA的二级结构和微环境。分子对接模拟表明二水土霉素结合在BSA的site Ⅰ(亚域ⅡA)疏水腔中。 相似文献
11.
Our previous experimental results have shown that ergosta‐4,6,8(14),22‐tetraen‐3‐one (ergone) is one of the main bioactive components of Polyporus umbellatus. The efficacy of ergone binding to human serum albumin (HSA) is critical for pharmacokinetic behavior of ergone. The interactions between ergone and HSA under simulative physiological conditions were investigated by the methods of fluorescence spectroscopy, absorption and circular dichroism spectroscopy. Fluorescence data revealed that the fluorescence quenching of HSA by ergone was the result of the formation of the ergone‐HSA complex. According to the modified Stern‐Volmer equation, the binding constants (Ka) between ergone and HSA were determined. The thermodynamic parameters, enthalpy change (ΔH) and entropy change (ΔS) for the reaction were calculated to be 0.989 kJ mol‐1 and 11.214 J mol‐1 K‐1, indicating that the hydrogen bonds and hydrophobic interactions played a dominant role in the binding of ergone to HSA. The conformational investigation showed that the presence of ergone decreased the α‐helical content of HSA and induced the slight unfolding of the polypeptides of protein. Furthermore, displacement experiments using warfarin and ibuprofen indicated that ergone could bind to site I of HSA, which was also in agreement with the results of the molecular modeling. 相似文献
12.
长春新碱与人血清白蛋白的相互作用研究 总被引:7,自引:1,他引:6
利用荧光和圆二色光谱研究了长春新碱(VCR)与人血清白蛋白(HSA)之间的相互作用. 通过荧光猝灭测得在288, 298和308 K时, VCR与HSA的结合常数K分别为2.14×104, 1.73×104 和1.35×104 L•mol-1, 表明VCR与HSA间具有较强的结合作用, 属于静态猝灭. 计算出焓变(ΔH)为 -17.38 kJ•mol-1, 熵变(ΔS)为22.62 J•mol-1•K-1, 结合分子模型理论计算的结果, 表明VCR与HSA相互作用时在色氨酸(Trp) 214残基和VCR分子中吲哚基间作用力以疏水作用力为主, 但在 VCR和HSA 分子间以静电引力为主. 圆二色光谱(CD)的数据表明相互作用后HSA的二级结构发生了改变:HSA的α-螺旋的含量从51.7%下降到32.9%, β-折叠的含量增加了9.2%. 相似文献
13.
Fengling Cui Yinghua Yan Qiangzhai Zhang Xiaojun Yao Guirong Qu Yan Lu 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,74(4):964-971
This study was designed to examine the interaction of 8-bromoadenosine with human serum albumin (HSA) by fluorescence spectroscopy in combination with molecular modeling under simulative physiological conditions. The results of fluorescence measurements indicate that 8-bromoadenosine has a strong ability to quench the intrinsic fluorescence of HSA through static quenching procedure. The binding constants (K) at different temperatures and thermodynamic parameters, enthalpy changes (ΔH) and entropy changes (ΔS) were calculated according to the fluorescence data. The results showed that the hydrophobic force played the major role in the binding of 8-bromoadenosine to HSA. The fluorescence experimental results were in agreement with the results obtained by molecular modeling study. The effects of some normal positive and negative ions on the binding constants were also discussed. Moreover, the synchronous fluorescence technique was used to characterize the interaction of 8-bromoadenosine to HSA and successfully applied to determine the total proteins in human serum, urine and saliva samples at room temperature under the optimum conditions with a wide linear range and satisfactory results. 相似文献
14.
The interaction between vinpocetine(VPC) and human serum albumin(HSA) in physiological buffer(pH 7.40) was investigated by fluorescence,FT-IR,UV-vis absorption and molecular modeling.VPC effectively quenched the intrinsic fluorescence of HSA via static quenching.The binding site number n and apparent binding constant K_a,corresponding thermodynamic parametersΔG,ΔH andΔS at different temperatures were calculated.The synchronous fluorescence and FT-IR spectra were used to investigate the structural change of HSA molecules with addition of VPC.Molecular modeling indicated that VPC could bind to the site I of HSA and hydrophobic interaction was the major acting force,which was in agreement with the binding mode study. 相似文献
15.
Fengling Cui Junli Wang Yanrui Cui Jianping Li Yan Lu Jing Fan Xiaojun Yao 《Analytical sciences》2007,23(6):719-725
The binding of N-(p-ethoxy-phenyl)-N'-(1-naphthyl)thiourea (EPNT) to human serum albumin (HSA) was investigated under simulative physiological conditions by fluorescence spectra in combination with UV absorption spectroscopy and a molecular modeling method. A strong fluorescence quenching reaction of EPNT to HSA was observed, and the quenching mechanism was suggested to be static quenching according to the Stern-Volmer equation. The binding constants (K) at different temperatures as well as thermodynamic parameters, enthalpy change (DeltaH) and entropy change (DeltaS), were calculated according to relevant fluorescent data and the vant' Hoff equation. This indicated that a hydrophobic interaction was a predominant intermolecular force for stabilizing the complex, which is in agreement with the results of molecule modeling study. The effects of energy transfer and other ions on the binding constant were considered. In addition, synchronous fluorescence technology was successfully applied to the determination of HSA added into the EPNT solution. 相似文献
16.
Jing Zhang Hui-Hui Sun Ye-Zhong Zhang Li-Yun Yang Jie Dai Yi Liu 《Journal of solution chemistry》2012,41(3):422-435
In this work, the interaction between indomethacin (IM) and human serum albumin (HSA) under simulative physiological conditions
was investigated by the methods of fluorescence spectroscopy, circular dichroism (CD) spectroscopy, and molecular modeling.
The experiment results showed that the fluorescence quenching of HSA by IM was a result of the formation of an IM–HSA complex
and the corresponding association constants (K
a) between IM and HSA at four different temperatures were determined according to the modified Stern–Volmer equation. The resulting
thermodynamic parameters ΔG, ΔH, and ΔS at different temperatures indicate that the hydrophobic force plays a major role for IM–HSA association, but hydrogen bonds
also could not be excluded. A molecular modeling study further confirmed the binding mode and indicated that the binding of
IM to HSA primarily takes place in sub-domain IIA (site I). The conformational investigation showed that the presence of IM
decreased the α-helical content of HSA and induced slight unfolding of the polypeptides of protein, which confirmed that some microenvironmental
and conformational changes occur for HSA molecules. 相似文献
17.
Wanju Zhang Xujie Xiong Fang Wang Yushu Ge Yi Liu 《Journal of solution chemistry》2013,42(6):1194-1206
Ronidazole (RNZ) is widely used for the therapeutic treatment of farmed animals and is suspected of being a human carcinogen and mutagen. The interaction between RNZ and human serum albumin (HSA) was investigated systematically by fluorescence spectroscopy, synchronous fluorescence, three-dimensional fluorescence, CD spectroscopy, UV–vis absorption spectroscopy and a molecular docking study. The results indicate that the probable quenching mechanism of HSA by RNZ is dynamic quenching. The corresponding thermodynamic parameters, such as ΔH, ΔS and ΔG, etc., were calculated according to the van’t Hoff equation. The results indicate that the forces acting between RNZ and HSA are mainly hydrogen bonds and van der Waals forces. The conformational changes in the interaction were studied by synchronous fluorescence, CD spectroscopy and three-dimensional fluorescence spectra. The results reveal that the microenvironment and conformation of HSA has been changed. A molecular modeling study further confirmed the binding mode obtained by the experimental studies. 相似文献
18.
Jinhua Li Cuiling Ren Yaheng Zhang Xiaoyan Liu Xiaojun Yao Zhide Hu 《Journal of Molecular Structure》2008,885(1-3):64-69
The interaction between Puerarin with human serum albumin has been studied for the first time by spectroscopic methods including fluorescence quenching technology, circular dichroism (CD) spectroscopy and Fourier transform infrared (FT-IR) spectroscopy under simulative physiological conditions. The results of fluorescence titration revealed that Puerarin can strongly quench the intrinsic fluorescence of HSA by static quenching and there is a single class of binding site on HSA. In addition, the studies of CD spectroscopy and FT-IR spectroscopy showed that the binding of Puerarin to HSA changed slightly molecular conformation of HSA. Furthermore, the thermodynamic functions ΔH0 and ΔS0 for the reaction were calculated to be −9.067 kJ mol−1 and 54.315 J mol−1 K−1 according to van’t Hoff equation. These data suggested that both hydrogen bond and hydrophobic interaction play a major role in the binding of Puerarin to HSA, which is in good agreement with the result of molecular modeling study. 相似文献
19.
Ali Jahanban-Esfahlan Soodabeh Davaran Ali A. Moosavi-Movahedi Siavoush Dastmalchi 《Journal of the Iranian Chemical Society》2017,14(7):1527-1540
The interaction between juglone at the concentration range of 10–110 µM and bovine serum albumin (BSA) or human serum albumin (HSA) at the constant concentration of 11 µM was investigated by fluorescence and UV absorption spectroscopy under physiological-like condition. Performing the experiments at different temperatures showed that the fluorescence intensity of BSA/HSA was decreased in the presence of juglone by a static quenching mechanism due to the formation of the juglone–protein complex. The binding constant for the interaction was in the order of 103 M?1, and the number of binding sites for juglone on serum albumins was determined to be equal to one. The thermodynamic parameters including enthalpy (ΔH), entropy (ΔS) and Gibb’s free energy (ΔG) changes were obtained by using the van’t Hoff equation. These results indicated that van der Waals force and hydrogen bonding were the main intermolecular forces stabilizing the complex in a spontaneous association reaction. Moreover, the interaction of BSA/HSA with juglone was verified by UV absorption spectra and molecular docking. The results of synchronous fluorescence, UV–visible and CD spectra demonstrated that the binding of juglone with BSA/HSA induces minimum conformational changes in the structure of albumins. The increased binding affinity of juglone to albumin observed in the presence of site markers (digoxin and ibuprofen) excludes IIA and IIIA sites as the binding site of juglone. This is partially in agreement with the results of molecular docking studies which suggests sub-domain IA of albumin as the binding site. 相似文献
20.
Crytotanshinone (CTSO) is a Chinese herbal medicine active ingredient isolated from Salvia miltiorrhiza. In this work, the interaction of CTSO and human serum albumin (HSA) was studied by fluorescence spectra, ultraviolet spectra, circular dichroism (CD) spectra, molecular probe and molecular modeling methods. The results showed that the endogenous fluorescence of HSA was quenched by CTSO through a static mechanism. The number of binding sites, equilibrium constants, and thermodynamic parameters of the reaction were calculated at three different temperatures. The positive enthalpy change (ΔHθ) and entropy change (ΔSθ) revealed that the interaction was an endothermic as well as an entropy-driven process, where hydrophobic power played the major role in stabilizing the structure of the new complex. Site-selective binding experiments were carried out using warfarin and ibuprofen as probes, which proved that CTSO binds to Sudlow’s site II in subdomain IIIA of the HSA molecule. Circular dichroism (CD) spectra was employed to detect the α-helix and β-strand contents in HSA before and after the binding of CTSO. Based on the experimental results, the structure of the CTSO–HSA complex was calculated by docking CTSO to the proven site using molecular modeling. The study obtained comprehensive information on structure and thermodynamics, which is essential for understanding the bioaffinity, delivery process and pharmacological mechanism. 相似文献