The interaction of ruthenium polypyridyl complex with DNA has been studied by isothermal titration calorimetry (ITC). The results show that complex [Ru(phen)2PMIP]2+ {phen=1,10-phenanthroline, PMIP=2-(4-methylphenyl)i...The interaction of ruthenium polypyridyl complex with DNA has been studied by isothermal titration calorimetry (ITC). The results show that complex [Ru(phen)2PMIP]2+ {phen=1,10-phenanthroline, PMIP=2-(4-methylphenyl)imidazo1,10-phenanthroline} interacts with calf thymus DNA (CT DNA) in terms of a model for a single set of identical sites through intercalation. The results are in agreement with our previous observations from spectroscopic methods and viscosity measurements. In addition, the results further show that the driving force for DNA binding with the complex is mainly driven by the enthalpy changes, and the contribution from the entropy changes to this driving force is negligible.展开更多
Metallothionein, a class of low molecular weight, metal- and cysteine-rich Proteins, are postulated to play a central role in metal-related biological processes such as the detoxification of Cd2+and Pb2+. The thermal ...Metallothionein, a class of low molecular weight, metal- and cysteine-rich Proteins, are postulated to play a central role in metal-related biological processes such as the detoxification of Cd2+and Pb2+. The thermal Properties of the interactions of rabbit liver Zn7MT2 and apo-MT2 with Cd2+ and Pb2+ were studied using isothermal titration calorimeter. The same product Cd7MT formed in the reactions of Cd2+ with Zn7MT2 and apo-MT2, while the reactions of Ph2+ with Zn7MT2 and apo-MT2 Produced two MT species Ph7MT and Ph7MT’. The thermodynamic parameters （△H、 △G、 △S, etc. ） for the reactions of MT with 1 mol metal ions were measured at 293. 15 K, pH 4.70. All of these reachons are spontaneous, exothermic processes. The values of △G and K show that Cd2+ is more affinitive to MT than Ph2+. The equilibrium constants K of the replacement reactions of Zn7MT2 by 1 mol Cd2+ and Pb2+ are 2. 7×105 and 1. 3×105 respectively, that means the concentrations of free Cd2+ and Pb2+ are depressed to about 1. 0×10-5 after the reactions with Zn7MT2. These data can be used to evaluate quantitatively the ability of MT in Cd2+ and Ph2+ detoxificatio.展开更多
目的模拟人体生理条件(p H 7.4)下阿托伐他汀(atorvastatin)和人血清白蛋白(HSA)的相互作用的过程。方法采用圆二色谱、荧光光谱、等温滴定量热法和分子对接模拟法,测定结合方式、结合位点数、热力学参数和分子结合距离等相关信息。结果...目的模拟人体生理条件(p H 7.4)下阿托伐他汀(atorvastatin)和人血清白蛋白(HSA)的相互作用的过程。方法采用圆二色谱、荧光光谱、等温滴定量热法和分子对接模拟法,测定结合方式、结合位点数、热力学参数和分子结合距离等相关信息。结果在25℃下,随着atorvastatin逐渐加入到HSA中,α-螺旋含量从58.34%逐渐减少到28.13%(Catorvastatin/CHSA=10.0);atorvastatin以静态淬灭的方式淬灭了HSA的内源性荧光;通过疏水-疏水和氢键作用结合了血清白蛋白且结合比为1∶1;分子对接结果表明,与HSA最有可能的结合位点为214位色氨酸残基附近。结论为阐述他汀类药物的药代动力学行为机制提供科学依据。展开更多
文摘The interaction of ruthenium polypyridyl complex with DNA has been studied by isothermal titration calorimetry (ITC). The results show that complex [Ru(phen)2PMIP]2+ {phen=1,10-phenanthroline, PMIP=2-(4-methylphenyl)imidazo1,10-phenanthroline} interacts with calf thymus DNA (CT DNA) in terms of a model for a single set of identical sites through intercalation. The results are in agreement with our previous observations from spectroscopic methods and viscosity measurements. In addition, the results further show that the driving force for DNA binding with the complex is mainly driven by the enthalpy changes, and the contribution from the entropy changes to this driving force is negligible.
文摘Metallothionein, a class of low molecular weight, metal- and cysteine-rich Proteins, are postulated to play a central role in metal-related biological processes such as the detoxification of Cd2+and Pb2+. The thermal Properties of the interactions of rabbit liver Zn7MT2 and apo-MT2 with Cd2+ and Pb2+ were studied using isothermal titration calorimeter. The same product Cd7MT formed in the reactions of Cd2+ with Zn7MT2 and apo-MT2, while the reactions of Ph2+ with Zn7MT2 and apo-MT2 Produced two MT species Ph7MT and Ph7MT’. The thermodynamic parameters （△H、 △G、 △S, etc. ） for the reactions of MT with 1 mol metal ions were measured at 293. 15 K, pH 4.70. All of these reachons are spontaneous, exothermic processes. The values of △G and K show that Cd2+ is more affinitive to MT than Ph2+. The equilibrium constants K of the replacement reactions of Zn7MT2 by 1 mol Cd2+ and Pb2+ are 2. 7×105 and 1. 3×105 respectively, that means the concentrations of free Cd2+ and Pb2+ are depressed to about 1. 0×10-5 after the reactions with Zn7MT2. These data can be used to evaluate quantitatively the ability of MT in Cd2+ and Ph2+ detoxificatio.
基金supported by the National Natural Science Foundation of China(21203166,21473157)Natural Science Foundation of Zhejiang Province,China(LY16B030001)Food Science and Engineering the Most Important Discipline of Zhejiang Province,China(JYTsp2014111)~~
文摘目的模拟人体生理条件(p H 7.4)下阿托伐他汀(atorvastatin)和人血清白蛋白(HSA)的相互作用的过程。方法采用圆二色谱、荧光光谱、等温滴定量热法和分子对接模拟法,测定结合方式、结合位点数、热力学参数和分子结合距离等相关信息。结果在25℃下,随着atorvastatin逐渐加入到HSA中,α-螺旋含量从58.34%逐渐减少到28.13%(Catorvastatin/CHSA=10.0);atorvastatin以静态淬灭的方式淬灭了HSA的内源性荧光;通过疏水-疏水和氢键作用结合了血清白蛋白且结合比为1∶1;分子对接结果表明,与HSA最有可能的结合位点为214位色氨酸残基附近。结论为阐述他汀类药物的药代动力学行为机制提供科学依据。
基金supported by the National Natural Science Foundation of China(21273061,21573061)Scientific Research Project of Higher Education of Henan Province,China(17A150032)~~
