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氧化修饰低密度脂蛋白(oxidized low density lipoprotein,oxLDL)被认为是动脉硬化的关键致病因素。oxLDL的性能与其唯一的组成蛋白-载脂蛋白B-100(apoB-100)的二级结构即构象密切相关。荧光光谱和圆二色(circular dichroism,CD)光谱是研究蛋白质构象的有力手段,因此在oxLDL结构的研究中也有广泛的应用。本文综述了近年来荧光光谱和圆二色光谱在LDL氧化研究方面的应用, 并对今后的研究方向做了展望。 相似文献
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采用紫外光谱、荧光光谱结合亚甲基蓝荧光探针(MB)、圆二色谱(CD)以及分子模拟等技术研究了生理条件下杨梅素与小牛胸腺DNA(ct-DNA)的相互作用,探索了其可能的结合位点与作用机制。热力学参数显示ΔH0、ΔS0,说明杨梅素与ct-DNA通过氢键和范德华力发生相互作用。光谱研究显示,ct-DNA能够猝灭杨梅素的内源荧光,猝灭方式为静态猝灭,两者的结合常数为1.86×103mol-1,结合位点数为1。在竞争性实验中杨梅素未能将MB从MB-DNA复合体系中游离出来,说明其与ct-DNA的作用方式为沟槽结合。圆二色光谱研究表明,杨梅素的加入未能破坏ct-DNA的双螺旋结构,两者的作用方式为沟槽结合。进一步通过分子模拟研究得到杨梅素与DNA结合的最低能量构象,杨梅素A环7-O和B环3’-O分别与DNA的碱基DA18和DA6在边缘小沟处通过氢键结合,周围富含碱基A和T,与光谱学研究结果一致,结合距离分别为2.061和1.918。 相似文献
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基于大环多胺的新型线型聚合物的合成及与DNA相互作用的研究 总被引:3,自引:0,他引:3
设计合成了一种新型线形大环聚合多胺(POGEC),该聚合物可通过1,3-丙二醇二缩水甘油基醚和1,7-二(二乙氧磷酰基)-1,4,7,10-四氮杂环十二烷反应得到.琼脂糖凝胶电泳和电子扫描光谱(SEM)显示POGEC与DNA有很强的结合能力.当生理浓度的氯化钠溶液加入到已经形成的POGEC/DNA复合物中,DNA可被有效释放.通过荧光光谱测量了POGEC与DNA的结合能力及紧缩能力.圆二色光谱表明POGEC的强结合力并未改变DNA的构象. 相似文献
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《理化检验(化学分册)》2016,(7)
采用荧光光谱、紫外-可见吸收光谱、红外光谱和圆二色光谱研究了3-氨基-4-二甲氨基-N-丁基-1.8-萘酰亚胺(ADBN)与牛血清白蛋白(BSA)结合反应的特征。荧光光谱与紫外-可见吸收光谱表明,ADBN使BSA荧光猝灭的机理为静态猝灭。根据热力学参数判断ADBN与BSA主要是通过氢键和范德华力结合,结合距离为4.08 nm。同步荧光光谱、圆二色光谱以及红外光谱表明,结合过程中BSA的构象发生了变化。 相似文献
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利用荧光猝灭光谱、同步荧光光谱、三维荧光光谱、紫外-可见吸收光谱及圆二色谱法研究了磺胺甲恶唑(Sulfamethoxazole,SMX)、磺胺二甲嘧啶(Sulfamethazine,SMZ)对牛血清白蛋白(Bovine serum albumin,BSA)结构的影响。荧光猝灭实验结果表明SMX和SMZ可以使BSA发生荧光猝灭;通过同步荧光光谱、三维荧光光谱和紫外-可见光谱实验数据定性的证实了SMX和SMZ的加入会使BSA的构象发生变化,并且通过紫外-可见光谱的实验结果可知SMX和SMZ与BSA之间的作用机理为静态猝灭。此外,由圆二色谱法得到的定量结果可知:当SMX或SMZ与BSA之间的摩尔浓度比为4∶1时,SMX可使BSA的α-螺旋结构含量由53.77%降低到51.82%;SMZ可使BSA的α-螺旋结构含量由53.77%降低到47.59%。 相似文献
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在模拟人体生理条件下,采用紫外光谱、荧光光谱、同步荧光光谱、三维荧光光谱和圆二色谱等方法,以纳米Ti O2作对照,研究GR-Ti O2与溶菌酶(LYSO)的相互作用,通过酶活性实验测定GR-Ti O2对LYSO活性的影响。荧光光谱结果表明GR-Ti O2与LYSO发生了相互作用,导致LYSO内源荧光猝灭,猝灭机制为静态猝灭,作用力类型为氢键和范德华力,与纳米Ti O2研究结果一致。同步荧光与圆二色谱结果进一步表明GR-Ti O2对LYSO的构象影响更大。酶活性实验结果表明GR-Ti O2对LYSO的活性抑制作用强于纳米Ti O2。 相似文献
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采用荧光及紫外光谱研究了1-酮-2-(对二甲氨基苯亚甲基)-四氢萘(KDTN)与人血清白蛋白(HSA)相互作用的光谱特性。 结果表明,静态猝灭和非辐射能量转移是导致KDTN对HSA荧光猝灭的主要原因。 测得17、27和37 ℃ 3个温度下的结合常数KA分别为1.633×108、0.7998×108和0.347×108 L/mol,结合位点数n分别为1.7、1.6和1.7;据Forster偶极 偶极非辐射能量转移理论,计算得到KDTN与HSA在3个温度下的作用距离r分别为2.64、2.59和2.64 nm;能量转移效率E分别为0.5100、0.4797和0.4210。 热力学参数表明,二者主要以范德华力或氢键结合;用同步荧光技术研究了KDTN对HSA构象的影响,结果表明,KDTN的加入对HSA构象影响不大。 相似文献
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利用手持技术改进测定乙醇分子结构实验 总被引:1,自引:0,他引:1
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。 相似文献
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Mustafa R. Ibrahim Zacharia A. Fataftah Paul von Ragu Schleyer Peter D. Stout 《Journal of computational chemistry》1987,8(8):1131-1138
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases. 相似文献
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由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。 相似文献
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V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1989,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988. 相似文献
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V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1988,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae. 相似文献
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Influence of viscosity of medium on processes of oxygen quenching of excited states of mesoporphyrin
E. I. Kapinus V. A. Ganzha B. M. Dzhagarov E. I. Sagun V. B. Pavlenko 《Theoretical and Experimental Chemistry》1989,25(2):146-151
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989. 相似文献