Fabrication And Control Of Artificial Coupled Enzyme System Based On DNA Self-assembly Nanostructures

Enzyme (Enzyme) is a polymer material with catalytic function and plays a very extensive capabilities in organisms. Regulation of signal transduction and cell activity were without enzymes. Most enzymes can significantly improve the catalytic reaction rate. For a long time, people have done a lot of research on the composition and the catalytic mechanism of enzymes. At present most enzymatic reactions are controlled by temperature, pH etc. However, most enzymatic reactions happen in narrow space of cells and the environment is tender. So it becomes a challenge that how to simulate the real environment of enzyme in cells and how to affect enzymatic reaction.DNA isnot merely a kind of biological macromolecules with genetic information, but also macromolecule nanomaterials With the development of DNA nanotechnology, based on sequence recognizing properties and precise nanoscale of DNA, people have built a series of good rigidity, shape control nanostructures with precise locating functions through specific design and self-assembly. Its rarely to regulate the form of DNA nanostructures using pH method and mostly adopting the method of heating or denaturant. So far, people have developed various complex2d and3d nanostructures. These DNA nanostructures can be used as a template to pattern proteins, metal nanoparticles and quantum dots precisely, and also widely used in biological chip, drug delivery, disease detection and other fields.In this paper, we developed a simple and effective method to research the formation of DNA origami structure by pH mediating. At the same time, our work constructed two-dimensional nanorectangles and three dimensional nanocylinder to assemble coupled enzyme system whose activities could be well studied. Our results show that the coupled enzymatic reaction in a certain distance of nanostructures is faster than in the free solution, nanocylinder provides a confined space environment compared to planar nanorectangles, we found that the enzymatic activity of coupled enzymes assembled in nanocylinders was higher than on nanorectangles. Besides, the enzymatic activity when coupled enzymes assembled inside the cylinder is higher than outside of the cylinder. Its probably that the wall function of nanocylinder limited intermediate diffusion inside the nanocylinder. We think this simulation could more fairly reflect actual crowded environment of enzyme in cells, which provides a great help for understanding of enzymatic reactions in cells. Moreover, it promotes the new developments in the field of DNA nanotechnology.