原子力显微镜观察DNA与内切酶的相互作用  

The Observation of Interaction Between DNA and Restriction Endonuclease with Atomic Force Microscope

作　　者：李超英[1] 黄先恺[1] 杨光参[2] 王艳伟[2] 

机构地区：[1]上饶师范学院物理与电子信息学院,江西上饶334001 [2]温州大学物理与电子信息工程学院,浙江温州325035

出　　处：《实验室研究与探索》2013年第8期13-16,共4页Research and Exploration In Laboratory

基　　金：国家自然科学基金项目(10974146;20934004);浙江省自然科学基金(Y6090222)资助项目

摘　　要：原子力显微镜是观察DNA与内切酶相互作用比较有效的研究技术。实验中,首先把不同种类的内切酶与DNA在含有钙离子的缓冲液中培育30 min,再通过原子力成像观察其相互作用后的复合物形貌。结果表明,二聚体内切酶EcoRV会结合到λ-DNA的单个识别位点,最终形成珠串状结构,而且对DNA有弯曲作用;另一类型四聚体内切酶BspMI除了可以结合λ-DNA的单个位点外,还可以结合2个识别位点而形成圆环状结构。此结果可以直观地观察到两种内切酶与DNA的作用形态,同时对DNA的弯曲与成环等结构给出直接证据。最后给出两种内切酶与DNA相互作用的模型图。Atomic force microscopy is effective research technology to observe the interaction between DNA and protein. First of all, in the experiment, the different kinds of enzyme and DNA were mixed in the buffer containing calcium ion, and were incubated for 30 minutes; Then the complex morphologies were observed by atomic force microscope. The results showed that dimer enzyme EcoRV may bind λ-DNA on single recognition sites to form the bead string structures and had bending action. Another tetramer enzyme BspMI not only combined single recognition of DNA, but also could combine the two recognition sites and form ring structure. The results could observe the interaction morphologies of two kind of enzyme and DNA directly, and gave direct evidence of DNA bending and ring structure. Finally, we gave the interaction model of two kinds of enzyme and DNA.

关 键 词：原子力显微镜 DNA 限制性内切酶 相互作用 

分 类 号：Q66[生物学—生物物理学] Q6-33