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Description
DNA has recently emerged as an extremely promising material to organize molecules on nanoscale. The reliability of base recognition, self-assembling behavior, and attractive structural properties of DNA are of unparalleled value in systems of this size. DNA scaffolds have already been used to organize a variety of molecules including nanoparticles

DNA has recently emerged as an extremely promising material to organize molecules on nanoscale. The reliability of base recognition, self-assembling behavior, and attractive structural properties of DNA are of unparalleled value in systems of this size. DNA scaffolds have already been used to organize a variety of molecules including nanoparticles and proteins. New protein-DNA bio-conjugation chemistries make it possible to precisely position proteins and other biomolecules on underlying DNA scaffolds, generating multi-biomolecule pathways with the ability to modulate inter-molecular interactions and the local environment. This dissertation focuses on studying the application of using DNA nanostructure to direct the self-assembly of other biomolecular networks to translate biochemical pathways to non-cellular environments. Presented here are a series of studies toward this application. First, a novel strategy utilized DNA origami as a scaffold to arrange spherical virus capsids into one-dimensional arrays with precise nanoscale positioning. This hierarchical self-assembly allows us to position the virus particles with unprecedented control and allows the future construction of integrated multi-component systems from biological scaffolds using the power of rationally engineered DNA nanostructures. Next, discrete glucose oxidase (GOx)/ horseradish peroxidase (HRP) enzyme pairs were organized on DNA origami tiles with controlled interenzyme spacing and position. This study revealed two different distance-dependent kinetic processes associated with the assembled enzyme pairs. Finally, a tweezer-like DNA nanodevice was designed and constructed to actuate the activity of an enzyme/cofactor pair. Using this approach, several cycles of externally controlled enzyme inhibition and activation were successfully demonstrated. This principle of responsive enzyme nanodevices may be used to regulate other types of enzymes and to introduce feedback or feed-forward control loops.
ContributorsLiu, Minghui (Author) / Yan, Hao (Thesis advisor) / Liu, Yan (Thesis advisor) / Chen, Julian (Committee member) / Zhang, Peiming (Committee member) / Arizona State University (Publisher)
Created2013
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Description
Single molecule identification is one essential application area of nanotechnology. The application areas including DNA sequencing, peptide sequencing, early disease detection and other industrial applications such as quantitative and quantitative analysis of impurities, etc. The recognition tunneling technique we have developed shows that after functionalization of the probe and substrate

Single molecule identification is one essential application area of nanotechnology. The application areas including DNA sequencing, peptide sequencing, early disease detection and other industrial applications such as quantitative and quantitative analysis of impurities, etc. The recognition tunneling technique we have developed shows that after functionalization of the probe and substrate of a conventional Scanning Tunneling Microscope with recognition molecules ("tethered molecule-pair" configuration), analyte molecules trapped in the gap that is formed by probe and substrate will bond with the reagent molecules. The stochastic bond formation/breakage fluctuations give insight into the nature of the intermolecular bonding at a single molecule-pair level. The distinct time domain and frequency domain features of tunneling signals were extracted from raw signals of analytes such as amino acids and their enantiomers. The Support Vector Machine (a machine-learning method) was used to do classification and predication based on the signal features generated by analytes, giving over 90% accuracy of separation of up to seven analytes. This opens up a new interface between chemistry and electronics with immediate implications for rapid Peptide/DNA sequencing and molecule identification at single molecule level.
ContributorsZhao, Yanan, 1986- (Author) / Lindsay, Stuart (Thesis advisor) / Nemanich, Robert (Committee member) / Qing, Quan (Committee member) / Ros, Robert (Committee member) / Zhang, Peiming (Committee member) / Arizona State University (Publisher)
Created2014
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Description
Deoxyribonucleic acid (DNA) has emerged as an excellent molecular building block for nanoconstruction in addition to its biological role of preserving genetic information. Its unique features such as predictable conformation and programmable intra- and inter-molecular Watson-Crick base pairing interactions make it a remarkable engineering material. A variety of convenient design

Deoxyribonucleic acid (DNA) has emerged as an excellent molecular building block for nanoconstruction in addition to its biological role of preserving genetic information. Its unique features such as predictable conformation and programmable intra- and inter-molecular Watson-Crick base pairing interactions make it a remarkable engineering material. A variety of convenient design rules and reliable assembly methods have been developed to engineer DNA nanostructures. The ability to create designer DNA architectures with accurate spatial control has allowed researchers to explore novel applications in directed material assembly, structural biology, biocatalysis, DNA

computing, nano-robotics, disease diagnosis, and drug delivery.

This dissertation focuses on developing the structural design rules for "static" DNA nano-architectures with increasing complexity. By using a modular self-assembly method, Archimedean tilings were achieved by association of different DNA motifs with designed arm lengths and inter-tile sticky end interactions. By employing DNA origami method, a new set of design rules was created to allow the scaffolds to travel in arbitrary directions in a designed geometry without local symmetry restrictions. Sophisticated wireframe structures of higher-order complexity were designed and constructed successfully. This dissertation also presents the use of "dynamic" DNA nanotechnology to construct DNA origami nanostructures with programmed reconfigurations.
ContributorsZhang, Fei (Author) / Yan, Hao (Thesis advisor) / Liu, Yan (Thesis advisor) / Gould, Ian (Committee member) / Zhang, Peiming (Committee member) / Arizona State University (Publisher)
Created2015
Description
DNA nanotechnology has been a rapidly growing research field in the recent decades, and there have been extensive efforts to construct various types of highly programmable and robust DNA nanostructures. Due to the advantage that DNA nanostructure can be used to organize biochemical molecules with precisely controlled spatial resolution, herein

DNA nanotechnology has been a rapidly growing research field in the recent decades, and there have been extensive efforts to construct various types of highly programmable and robust DNA nanostructures. Due to the advantage that DNA nanostructure can be used to organize biochemical molecules with precisely controlled spatial resolution, herein we used DNA nanostructure as a scaffold for biological applications. Targeted cell-cell interaction was reconstituted through a DNA scaffolded multivalent bispecific aptamer, which may lead to promising potentials in tumor therapeutics. In addition a synthetic vaccine was constructed using DNA nanostructure as a platform to assemble both model antigen and immunoadjuvant together, and strong antibody response was demonstrated in vivo, highlighting the potential of DNA nanostructures to serve as a new platform for vaccine construction, and therefore a DNA scaffolded hapten vaccine is further constructed and tested for its antibody response. Taken together, my research demonstrated the potential of DNA nanostructure to serve as a general platform for immunological applications.
ContributorsLiu, Xiaowei (Author) / Liu, Yan (Thesis advisor) / Chang, Yung (Thesis advisor) / Yan, Hao (Committee member) / Allen, James (Committee member) / Zhang, Peiming (Committee member) / Arizona State University (Publisher)
Created2012