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1.
Growth of Hydrophilic CuS Nanowires via DNA‐Mediated Self‐Assembly Process and Their Use in Fabricating Smart Hybrid Films for Adjustable Chemical Release
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Li Zhou Wei Li Zhaowei Chen Enguo Ju Prof. Dr. Jinsong Ren Prof. Dr. Xiaogang Qu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(7):2930-2935
Facile growth of CuS nanowires through self‐assembly and their application as building blocks for near‐infrared light‐responsive functional films have been demonstrated. It is found that DNA is a key factor in preparing the CuS material with defined nanostructure. An exclusive oriented self‐aggregate growth mechanism is proposed for the growth of the nanowires, which might have important implications for preparing advanced, sophisticated nanostructures based on DNA nanotechnology. By employing the hydrophilic CuS nanowire as an optical absorber and thermosensitive nanogel as guest reservoir inside alginate film, a new platform for the release of functional molecules has been set up. In vitro studies have shown that the hybrid film possesses excellent biocompatibility and the release rate of chemical molecules from the film could be controlled with high spatial and temporal precision. Our novel approach and the resulting outstanding combination of properties may advance both the fields of DNA nanotechnology and light‐responsive devices. 相似文献
2.
Hua Zuo Siyu Wu Mo Li Yulin Li Wen Jiang Chengde Mao 《Angewandte Chemie (International ed. in English)》2015,54(50):15118-15121
Programmed self‐assembly of nucleic acids (DNA and RNA) is an active research area as it promises a general approach for nanoconstruction. Whereas DNA self‐assembly has been extensively studied, RNA self‐assembly lags much behind. One strategy to boost RNA self‐assembly is to adapt the methods of DNA self‐assembly for RNA self‐assembly because of the chemical and structural similarities of DNA and RNA. However, these two types of molecules are still significantly different. To enable the rational design of RNA self‐assembly, a thorough examination of their likes and dislikes in programmed self‐assembly is needed. The current work begins to address this task. It was found that similar, two‐stranded motifs of RNA and DNA lead to similar, but clearly different nanostructures. 相似文献
3.
During the development of structural DNA nanotechnology, the emerging of scaffolded DNA origami is marvelous. It utilizes DNA double helix inherent specificity of Watson‐Crick base pairing and structural features to create self‐assembling structures at the nanometer scale exhibiting the addressable character. However, the assembly of DNA origami is disorderly and unpredictable. Herein, we present a novel strategy to assemble the DNA origami using rolling circle amplification based DNA nanoribbons as the linkers. Firstly, long single‐stranded DNA from Rolling Circle Amplification is annealed with several staples to form kinds of DNA nanoribbons with overhangs. Subsequently, the rectangle origami is formed with overhanged staple strands at any edge that would hybridize with the DNA nanoribbons. By mixing them up, we illustrate the one‐dimensional even two‐dimensional assembly of DNA origami with good orientation. 相似文献
4.
Cheng Tian Xiang Li Zhiyu Liu Prof. Wen Jiang Prof. Guansong Wang Prof. Chengde Mao 《Angewandte Chemie (International ed. in English)》2014,53(31):8041-8044
Tile‐based self‐assembly is a powerful method in DNA nanotechnology and has produced a wide range of well‐defined nanostructures. But the resulting structures are relatively simple. Increasing the structural complexity and the scope of the accessible structures is an outstanding challenge in molecular self‐assembly. A strategy to partially address this problem by introducing flexibility into assembling DNA tiles and employing directing agents to control the self‐assembly process is presented. To demonstrate this strategy, a range of DNA nanocages have been rationally designed and constructed. Many of them can not be assembled otherwise. All of the resulting structures have been thoroughly characterized by gel electrophoresis and cryogenic electron microscopy. This strategy greatly expands the scope of accessible DNA nanostructures and would facilitate technological applications such as nanoguest encapsulation, drug delivery, and nanoparticle organization. 相似文献
5.
Structural varieties of selectively mixed G‐ and C‐rich short DNA sequences studied with electrospray ionization mass spectrometry
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Yanwei Cao Shang Gao Caijin Li Yuting Yan Bing Wang Xinhua Guo 《Journal of mass spectrometry : JMS》2016,51(10):931-937
Short guanine(G)‐repeat and cytosine(C)‐repeat DNA strands can self‐assemble to form four‐stranded G‐quadruplexes and i‐motifs, respectively. Herein, G‐rich and C‐rich strands with non‐G or non‐C terminal bases and different lengths of G‐ or C‐repeats are mixed selectively in pH 4.5 and 6.7 ammonium acetate buffer solutions and studied by electrospray ionization mass spectrometry (ESI‐MS). Various strand associations corresponding to bi‐, tri‐ and tetramolecular ions are observed in mass spectra, indicating that the formation of quadruplex structures is a random strand by strand association process. However, with increasing incubation time for the mixtures, initially associated hybrid tetramers will transform into self‐assembled conformations, which is mainly driven by the structural stability. The melting temperature values of self‐assembled quadruplexes suggest that the length of G‐repeats or C‐repeats shows more significant effect on the stability of quadruplex structures than that of terminal residues. Accordingly, we can obtain the self‐associated tetrameric species generated from the mixtures of various homologous G‐ or C‐strands efficiently by altering the length of G‐ or C‐repeats. Our studies demonstrate that ESI‐MS is a very direct, fast and sensitive tool to provide significant information on DNA strand associations and stoichiometric transitions, particularly for complex mixtures. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
6.
A hemin‐binding DNA G‐quadruplex (also known as a hemin aptamer or DNAzyme) has been previously reported to be able to enhance the peroxidase activity of hemin. In this work, we described a DNAzyme structure that had an effector‐recognizing part appearing as a single stranded DNA linkage flanked by two split G‐quadruplex halves. Hybridization of the single stranded part in the enzyme with a perfectly matched DNA strand (effector) formed a rigid DNA duplex between the two G‐quadruplex halves and thus efficiently suppressed the enzymatic activity of the G‐quadruplex/hemin complex, while the mismatched effector strand was not able to regulate the peroxidase activity effectively. With 2,2′‐azinobis(3‐ethylbenzthiazoline)‐6‐sulfonic acid (ABTS) as an oxidizable substrate, we were able to characterize the formation of the re‐engineered G‐quadruplex/hemin complex and verify its switchable peroxidase activity. Our results show that the split G‐quadruplex is an especially useful module to design low‐cost and label‐free sensors toward various biologically or environmentally interesting targets. 相似文献
7.
Dr. Miguel Angel Aleman‐Garcia Ron Orbach Prof. Itamar Willner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(19):5619-5624
Programmed nucleic acid sequences undergo K+ ion‐induced self‐assembly into G‐quadruplexes and separation of the supramolecular structures by the elimination of K+ ions by crown ether or cryptand ion‐receptors. This process allows the switchable formation and dissociation of the respective G‐quadruplexes. The different G‐quadruplex structures bind hemin, and the resulting hemin–G‐quadruplex structures reveal horseradish peroxidase DNAzyme catalytic activities. The following K+ ion/receptor switchable systems are described: 1) The K+‐induced self‐assembly of the Mg2+‐dependent DNAzyme subunits into a catalytic nanostructure using the assembly of G‐quadruplexes as bridging unit. 2) The K+‐induced stabilization of the anti‐thrombin G‐quadruplex nanostructure that inhibits the hydrolytic functions of thrombin. 3) The K+‐induced opening of DNA tweezers through the stabilization of G‐quadruplexes on the “tweezers’ arms" and the release of a strand bridging the tweezers into a closed structure. In all of the systems reversible, switchable, functions are demonstrated. For all systems two different signals are used to follow the switchable functions (fluorescence and the catalytic functions of the derived hemin–G‐quadruplex DNAzyme). 相似文献
8.
Yang Qianfan Xiang Junfeng Yang Shu Zhou Qiuju Li Qian Guan Aijiao Zhang Xiufeng Zhang Hong Tang Yalin Xu Guangzhi 《中国化学》2010,28(7):1126-1132
Single‐stranded telomeric DNA tends to form a four‐base‐paired planar structure termed G‐quadruplex. Although kinds of G‐quadruplex structures in vitro have been documented in the presence of potassium or sodium, recognition of these DNA motifs (both in vitro and in vivo) is still an important issue in understanding the biological function of the G‐quadruplex structures in telomeres as well as developing anticancer agents. Herein we address this important question through the distinctive properties of a supramolecular system of cyanine dye 3,3′‐di(3‐sulfopropyl)‐4,5,4′,5′‐dibenzo‐9‐methyl‐thiacarbocyanine triethylammonium salt (MTC) upon binding to different DNA motifs. Interaction of MTC with hybrid/mixed G‐quadruplex results in a set of unique spectrophotometric signatures which are completely different from those arising from binding to other DNA motifs. Furthermore, such feature could be extended to map the locations of DNAs on interface. Linear duplex and mixed G‐quadruplex in human telomeres assembled on Au film and stained by MTC were directly recognized by confocal laser scanning microscopy (CLSM). All results suggested that MTC supramolecular system may be a good probe of specific G‐quadruplex structure. 相似文献
9.
Dr. David A. Rusling Arun Richard Chandrasekaran Dr. Yoel P. Ohayon Prof. Dr. Tom Brown Prof. Dr. Keith R. Fox Dr. Ruojie Sha Prof. Dr. Chengde Mao Prof. Dr. Nadrian C. Seeman 《Angewandte Chemie (International ed. in English)》2014,53(15):3979-3982
DNA is a very useful molecule for the programmed self‐assembly of 2D and 3D nanoscale objects. 1 The design of these structures exploits Watson–Crick hybridization and strand exchange to stitch linear duplexes into finite assemblies. 2 – 4 The dimensions of these complexes can be increased by over five orders of magnitude through self‐assembly of cohesive single‐stranded segments (sticky ends). 5 , 6 Methods that exploit the sequence addressability of DNA nanostructures will enable the programmable positioning of components in 2D and 3D space, offering applications such as the organization of nanoelectronics, 7 the direction of biological cascades, 8 and the structure determination of periodically positioned molecules by X‐ray diffraction. 9 To this end we present a macroscopic 3D crystal based on the 3‐fold rotationally symmetric tensegrity triangle 3 , 6 that can be functionalized by a triplex‐forming oligonucleotide on each of its helical edges. 相似文献
10.
Katherine G. Young Behnam Najafi William M. Sant Sonia Contera Ard A. Louis Jonathan P. K. Doye Andrew J. Turberfield Jonathan Bath 《Angewandte Chemie (International ed. in English)》2020,59(37):15942-15946
DNA self‐assembly allows the construction of nanometre‐scale structures and devices. Structures with thousands of unique components are routinely assembled in good yield. Experimental progress has been rapid, based largely on empirical design rules. Herein, we demonstrate a DNA origami technique designed as a model system with which to explore the mechanism of assembly. The origami fold is controlled through single‐stranded loops embedded in a double‐stranded DNA template and is programmed by a set of double‐stranded linkers that specify pairwise interactions between loop sequences. Assembly is via T‐junctions formed by hybridization of single‐stranded overhangs on the linkers with the loops. The sequence of loops on the template and the set of interaction rules embodied in the linkers can be reconfigured with ease. We show that a set of just two interaction rules can be used to assemble simple T‐junction origami motifs and that assembly can be performed at room temperature. 相似文献
11.
Mark A. Boerneke Sergey M. Dibrov Thomas Hermann 《Angewandte Chemie (International ed. in English)》2016,55(12):4097-4100
RNA nanotechnology uses RNA structural motifs to build nanosized architectures that assemble through selective base‐pair interactions. Herein, we report the crystal‐structure‐guided design of highly stable RNA nanotriangles that self‐assemble cooperatively from short oligonucleotides. The crystal structure of an 81 nucleotide nanotriangle determined at 2.6 Å resolution reveals the so‐far smallest circularly closed nanoobject made entirely of double‐stranded RNA. The assembly of the nanotriangle architecture involved RNA corner motifs that were derived from ligand‐responsive RNA switches, which offer the opportunity to control self‐assembly and dissociation. 相似文献
12.
Dr. Romain Haudecoeur Loic Stefan Dr. David Monchaud 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(38):12739-12747
Natural G‐quartets, a cyclic and coplanar array of four guanine residues held together through a Watson–Crick/Hoogsteen hydrogen‐bond network, have received recently much attention due to their involvement in G‐quadruplex DNA, an alternative higher‐order DNA structure strongly suspected to play important roles in key cellular events. Besides this, synthetic G‐quartets (SQ), which artificially mimic native G‐quartets, have also been widely studied for their involvement in nanotechnological applications (i.e., nanowires, artificial ion channels, etc.). In contrast, intramolecular synthetic G‐quartets (iSQ), also named template‐assembled synthetic G‐quartets (TASQ), have been more sparingly investigated, despite a technological potential just as interesting. Herein, we report on a particular iSQ named PNADOTASQ, which demonstrates very interesting properties in terms of DNA and RNA interaction (notably its selective recognition of quadruplexes according to a bioinspired process) and catalytic activities, through its ability to perform peroxidase‐like hemin‐mediated oxidations either in an autonomous fashion (i.e., as pre‐catalyst for TASQzyme reactions) or in conjunction with quadruplex DNA (i.e., as enhancing agents for DNAzyme processes). These results provide a solid scientific basis for TASQ to be used as multitasking tools for bionanotechnological applications. 相似文献
13.
Metal‐Ion‐Triggered Exonuclease III Activity for the Construction of DNA Colorimetric Logic Gates
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Wan Gao Dr. Li Zhang Prof. Ru‐Ping Liang Prof. Jian‐Ding Qiu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(43):15272-15279
The logic system is obtained by using a series of double‐stranded (ds) DNA templates with mismatched base pairs (T–T or C–C) and ion‐modulated exonuclease III (Exo III) activity, in which the Exo III cofactors, Hg2+ and Ag+ ions, are used as inputs for the activation of the respective scission of Exo III based on the formation of T–Hg2+–T or C–Ag+–C base pairs. Additionally, two kinds of signal probes are utilized to transduce the logic operations. One is the two split G‐rich DNA strands that are used to design the OR, AND, INHIBIT, and XOR gates, whereas the other is the self‐assembled split G‐quadruplex structure to construct NOR, NAND, IMPLICATION, and XNOR operations based on DNA hybridization and strand displacement. In the presence of hemin, the split G‐quadruplex biocatalyzes the formation of a colored product, which is an output signal for the different logic gates. Thus, we have constructed a complete set of colorimetric DNA logic gates based on the Exo III and split G‐quadruplex for the first time. In addition, we are able to effortlessly recognize the logic output signals by the naked eye and their simplicity and cost‐effective design is the most apparent feature for the logic gates developed in this work. 相似文献
14.
Dr. Zengqi Xie Dr. Vladimir Stepanenko Dr. Krzysztof Radacki Prof. Dr. Frank Würthner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(23):7060-7070
Herein we report on structural, morphological, and optical properties of homochiral and heterochiral J‐aggregates that were created by nucleation–elongation assembly of atropo‐enantiomerically pure and racemic perylene bisimides (PBIs), respectively. Our detailed studies with conformationally stable biphenoxy‐bridged chiral PBIs by UV/Vis absorption, circular dichroism (CD) spectroscopy, and atomic force microscopy (AFM) revealed structurally as well as spectroscopically quite different kinds of J‐aggregates for enantiomerically pure and racemic PBIs. AFM investigations showed that enantiopure PBIs form helical nanowires of unique diameter and large length‐to‐width ratio by self‐recognition, while racemic PBIs provide irregular‐sized particles by self‐discrimination of the enantiomers at the stage of nucleation. Steady‐state fluorescence spectroscopy studies revealed that the photoluminescence efficiency of homochiral J‐aggregated nanowires (47±3 %) is significantly higher than that of heterochiral J‐aggregated particle‐like aggregates (12±3 %), which is explained in terms of highly ordered molecular stacking in one‐dimensional nanowires of homochiral J‐aggregates. Our present results demonstrate the high impact of homochirality on the construction of well‐defined nanostructures with unique optical properties. 相似文献
15.
Interactions of Pt‐ttpy with G‐Quadruplexes Originating from Promoter Region of the c‐myc Gene Deciphered by NMR and Gel Electrophoresis Analysis
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Dr. Marko Trajkovski Elodie Morel Dr. Florian Hamon Dr. Sophie Bombard Dr. Marie‐Paule Teulade‐Fichou Prof. Dr. Janez Plavec 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(21):7798-7807
16.
Direct and Single‐Molecule Visualization of the Solution‐State Structures of G‐Hairpin and G‐Triplex Intermediates
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Dr. Arivazhagan Rajendran Prof. Dr. Masayuki Endo Kumi Hidaka Prof. Dr. Hiroshi Sugiyama 《Angewandte Chemie (International ed. in English)》2014,53(16):4107-4112
We present the direct and single‐molecule visualization of the in‐pathway intermediates of the G‐quadruplex folding that have been inaccessible by any experimental method employed to date. Using DNA origami as a novel tool for the structural control and high‐speed atomic force microscopy (HS‐AFM) for direct visualization, we captured images of the unprecedented solution‐state structures of a tetramolecular antiparallel and (3+1)‐type G‐quadruplex intermediates, such as G‐hairpin and G‐triplex, with nanometer precision. No such structural information was reported previously with any direct or indirect technique, solution or solid‐state, single‐molecule or bulk studies, and at any resolution. Based on our results, we proposed a folding mechanism of these G‐quadruplexes. 相似文献
17.
Bo Li Chuchu Zhang Beibei Jiang Dr. Wei Han Prof. Zhiqun Lin 《Angewandte Chemie (International ed. in English)》2015,54(14):4250-4254
One‐dimensional nanowires enable the realization of optical and electronic nanodevices that may find applications in energy conversion and storage systems. Herein, large‐scale aligned DNA nanowires were crafted by flow‐enabled self‐assembly (FESA). The highly oriented and continuous DNA nanowires were then capitalized on either as a template to form metallic nanowires by exposing DNA nanowires that had been preloaded with metal salts to an oxygen plasma or as a scaffold to direct the positioning and alignment of metal nanoparticles and nanorods. The FESA strategy is simple and easy to implement and thus a promising new method for the low‐cost synthesis of large‐scale one‐dimensional nanostructures for nanodevices. 相似文献
18.
Xiao Xie Bina Choi Dr. Eric Largy Dr. Régis Guillot Dr. Anton Granzhan Dr. Marie‐Paule Teulade‐Fichou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(4):1214-1226
The interactions of three cationic distyryl dyes, namely 2,4‐bis(4‐dimethylaminostyryl)‐1‐methylpyridinium ( 1 a ), its derivative with a quaternary aminoalkyl chain ( 1 b ), and the symmetric 2,6‐bis(4‐dimethylaminostyryl)‐1‐methylpyridinium ( 2 a ), with several quadruplex and duplex nucleic acids were studied with the aim to establish the influence of the geometry of the dyes on their DNA‐binding and DNA‐probing properties. The results from spectrofluorimetric titrations and thermal denaturation experiments provide evidence that asymmetric (2,4‐disubstituted) dyes 1 a and 1 b bind to quadruplex DNA structures with a near‐micromolar affinity and a fair selectivity with respect to double‐stranded (ds) DNA [Ka(G4)/Ka(ds)=2.5–8.4]. At the same time, the fluorescence of both dyes is selectively increased in the presence of quadruplex DNAs (more than 80–100‐fold in the case of human telomeric quadruplex), even in the presence of an excess of competing double‐stranded DNA. This optical selectivity allows these dyes to be used as quadruplex‐DNA‐selective probes in solution and stains in polyacrylamide gels. In contrast, the symmetric analogue 2 a displays a strong binding preference for double‐stranded DNA [Ka(ds)/Ka(G4)=40–100), presumably due to binding in the minor groove. In addition, 2 a is not able to discriminate between quadruplex and duplex DNA, as its fluorescence is increased equally well (20–50‐fold) in the presence of both structures. This study emphasizes and rationalizes the strong impact of subtle structural variations on both DNA‐recognition properties and fluorimetric response of organic dyes. 相似文献
19.
Dr. Matteo Nadai Dr. Filippo Doria Dr. Luca Germani Prof. Sara N. Richter Prof. Mauro Freccero 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(6):2330-2334
A photoreactive molecular dye targeting the G‐quadruplex nucleic acid (G4) of the human telomeric sequence Tel22, and several mutated analogues, was activated by green light (λ=532 nm). Highly selective covalent modification of G4 versus single‐stranded and double‐stranded DNA was achieved with efficiency up to 64 %. The phenoxyl radical was generated and detected by laser‐flash photolysis as a reactive intermediate that targeted loop thymine residues. These insights may suggest a non‐invasive tool for selective nucleic acid tagging and “pull‐down” cellular applications. 相似文献
20.
Prof. Dr. Zhou Nie Pengfei Wang Cheng Tian Prof. Dr. Chengde Mao 《Angewandte Chemie (International ed. in English)》2014,53(32):8402-8405
Herein, we report a strategy for the synchronization of two self‐assembly processes to assemble stimulus‐responsive DNA nanostructures under isothermal conditions. We hypothesized that two independent assembly processes, when brought into proximity in space, could be synchronized and would exhibit positive synergy. To demonstrate this strategy, we assembled a ladderlike DNA nanostructure and a ringlike DNA nanostructure through two hybridization chain reactions (HCRs) and an HCR in combination with T‐junction cohesion, respectively. Such proximity‐induced synchronization adds a new element to the tool box of DNA nanotechnology. We believe that it will be a useful approach for the assembly of complex and responsive nanostructures. 相似文献