液体环境单分子免疫球蛋白G的原子力显微镜高分辨成像  

High-Resolution Imaging of Single-Molecule Immunoglobulin G Antibodies with Atomic Force Microscopy in Liquid

作　　者：赵志杰[1] 张萍[2] 杨家香[3] 郝长春[3] 周星飞[1] 李宾[4] 

机构地区：[1]宁波大学理学院,宁波315211 [2]内蒙古农业大学生命科学研究院,内蒙古010018 [3]陕西师范大学,物理学与信息技术学院,西安710062 [4]中国科学院上海应用物理研究所物理生物研究室,中国科学院微观界面物理与探测重点实验室,上海201800

出　　处：《分析化学》2016年第8期1215-1220,共6页Chinese Journal of Analytical Chemistry

基　　金：科技部973项目(Nos.2013CB932800,2012CB932600);国家自然科学基金(Nos.11375253,11474173,U1532260);中国科学院知识创新项目(KJCX2-EW-N03)资助

摘　　要：原子力显微镜技术(AFM)具有纳米级高分辨成像能力,是研究生物大分子结构和功能的重要工具之一。制备合适的样品是获取高分辨成像的关键要素。本研究结合DNA折纸技术,将抗原分子修饰在DNA折纸上,通过分子识别作用,抗体分子与抗原分子特异性结合,形成由DNA折纸和抗原抗体复合物构成的纳米结构。利用DNA折纸在云母表面上的吸附特点,使得抗体分子选择性地吸附在衬底表面上,由此获得了液体环境中的单个地高辛抗体免疫球蛋白G(Ig G)分子的"Y"超微结构形貌。本方法简单、方便,为AFM在单分子水平上检测和表征生物分子结构和功能提供帮助。Atomic force microscopy （ AFM） is one of important tools for studying the structure and function of biomolecules due to its nanoscale capability. A well prepared sample was the primary key issue for high-resolution imaging macromolecules. Here, by using self-assembly technology of DNA origami, antigens were modified on DNA origami. Afterward, antibodies reacted specifically with antigens by a molecular recognition way. Then, a nanostructure formed from DNA origami and antigen-antibody complexes. By the aid of adsorption character of DNA origami, individual antibodies could selectively adsorb on mica surface. As a result, the ultrastructural morphology image of a single IgG molecule, the characteristic“Y-shaped” domains, was resolved in liquid. The way for adsorbing biomolecules on the mica surface in a liquid environment was simple and convenient, and it may be useful to detect and measure biomoleculers at the singe-molecule level with AFM.

关 键 词：原子力显微术 单分子 高分辨成像 免疫球蛋白G DNA折纸技术 

分 类 号：Q-336[生物学]