Li Qi, Wu Guangqi, Wu Wei, Liang Xingguo
College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China.
Chembiochem. 2016 Jun 16;17(12):1127-31. doi: 10.1002/cbic.201600071. Epub 2016 May 23.
Topologically controlled DNA catenanes are promising elements for the construction of molecular machines but present a significant effort in DNA nanotechnology. We report an efficient approach for preparing linear three-ring catenanes (L3C) composed of single-stranded DNA. The linking number was strictly controlled by using short complementary regions (6 nt) between each two DNA rings. High efficiency of forming three-ring catenanes (yield as high as 63 %) was obtained by using an 80 nt oligonucleotide as the scaffold to draw close the three pre-rings for hybridization between short complementary DNA. After assembly, three pre-rings were closed by DNA ligation using three 12 nt oligonucleotides as splints to form interlocked three-ring catenanes. L3C nanostructures were imaged in air by AFM: the catenane exhibited a smooth circular shape and was arranged in a line with well-defined structure, as expected.
拓扑控制的DNA连环体是构建分子机器的有前景的元件，但在DNA纳米技术中需要付出巨大努力。我们报道了一种制备由单链DNA组成的线性三环连环体（L3C）的有效方法。通过在每两个DNA环之间使用短互补区域（6 nt）来严格控制连环数。使用80 nt寡核苷酸作为支架，拉近三个预环以进行短互补DNA之间的杂交，从而高效形成三环连环体（产率高达63%）。组装后，使用三个12 nt寡核苷酸作为夹板通过DNA连接封闭三个预环，以形成互锁的三环连环体。通过原子力显微镜（AFM）在空气中对L3C纳米结构进行成像：连环体呈现出光滑的圆形，并且如预期那样以结构明确的方式排列成一条线。
