【作者】 孟荣华；

【导师】 刘志国；

【作者基本信息】 东北林业大学 ， 生药学， 2010， 硕士

【摘要】 1、气相和液相条件下在云母表面对人体DNA拓扑异构酶I的原子力显微镜成像研究采用原子力显微镜(AFM)在气相和液相条件下观察了重组的人体DNA拓扑异构酶I(TOPOI)的形貌。低浓度(0.3U%μl)的TOPOI在云母表面吸附2h后,在液相和气相下成像,均可扫描得到完全分散的单个TOPOI,对气相和液相下扫描的图像进行了比较,结果显示两种环境下扫描得到的酶的形貌有所不同。高浓度(4U/μl)的TOPOI在吸附1.5h后可以在云母表面形成一层单分子蛋白膜,该蛋白膜具有良好的稳定性和平整度。2、人体拓扑异构酶I与DNA结合后在云母表面的成像研究采用Ni2将DNA固定在云母的表面,在气相条件下运用原子力显微镜对其进行了成像研究,对单个DNA分子进行了高分辨的观察。当使用高浓度DNA分子进行成像时,观察到了DNA网络结构和DNA膜状结构。TOPOI与DNA分子结合后,TOPOI分子可以连同DNA一起吸附到云母表面。3、微管蛋白聚合现象研究采用原子力显微镜和紫外可见分光光度计对微管蛋白聚合现象进行了研究,采用原子力显微镜在液相下扫描观察到了吸附在APTES-mica表面的微管；采用紫外可见分光光度计检测了微管蛋白聚合的动力学曲线。4、DNA在石墨表面的原子力显微镜成像研究采用原子力显微镜(AFM)、傅里叶变换红外光谱仪(FTIR)对胡敏酸在HOPG表面的吸附进行了研究,采用傅里叶变换红外的检测确认了胡敏酸在HOPG表面的吸附。通过原子力显微镜观察了胡敏酸水溶液及其在酸性及碱性条件下、以及它与无机盐作用后在HOPG表面的吸附现象,显微成像研究表明胡敏酸可在HOPG表面产生成膜现象。以胡敏酸膜为模板,可以吸附DNA分子。采用原子力显微镜观察到了吸附在胡敏酸膜表面的DNA分子。更多还原

【Abstract】 1、Imaging and Studying Human TopoisomeraseⅠon Mica Surfaces in Air and in Liquid by Atomic Force McroscopyThe topography of human topoisomeraseⅠ(TOPOI) on mica surfaces in air and in liquid has been studied by atomic force microscopy (AFM). After adsorption of the low concentration (0.3U/μl) TOPOI on mica surfaces for 2 hours, and then imaged in liquid and in air by AFM, well-separated single TOPOI was observed. The comparison of the results between scanning in liquid and in air was done, the sizes of TOPOI scanned in liquid and in air were different. After adsorption of the high concentration (4U/μl) TOPOI on mica surfaces for 1.5 hours, TOPOI monolayer can be formed.The produced TOPOI monolayer on mica was flat and exhibited good stability.2、Imaging Human TopoisomeraseⅠcombined with DNA on Mica Surfaces by Atomic Force MicroscopyDivalent cation Ni2+ has been used to immobilize the DNA molecules. The topography of DNA molecules has been observed by AFM. When using high DNA concentration for AFM imaging, DNA networks and DNA molecule films can be formed. After topoisomeraseⅠcombined with DNA, TOPOI and DNA can both absorbed on mica surfaces.3、Studies of the Tubulin PolymerizationThe tubulin polymerization has been studied by atomic force microscopy (AFM) and UV. The topography of microtubule absorbed on APTES-mica surfaces has been observed by AFM in liquid. The kinetic curves of the tubulin polymerization have been detected by UV.4、Imaging and Studying DNA on HOPG by Atomic Force MicroscopyThe adsorption of Humic acid on HOPG surfaces has been studied by Atomic Force Microscopy(AFM) and Fourier transform infrared spectrometer(FTIR).After the detection of FTIR, Humic acid has definitely adsorbed on HOPG surfaces.The topographies of Humic acid, HA in the acidic or alkaline conditions and the admixture of HA and salt on HOPG surfaces have been studied by AFM. The influences of salt and acidic or alkaline conditions have been studied. HA molecular film can be formed on HOPG surfaces. As a template, DNA molecule can be adsorbed on humic acid film. The DNA absorbed on HA molecular film has been observed by AFM.更多还原