Team:Yonsei Korea/Nanoscience
Introducing:
Our Team
According to statistics, 3.5 billion people, or half the world's population, rely on rice for at least 20% of their caloric intake. More so, according to our background research, the biggest threat rice farmers face is Magnaporthe oryzae, more commonly known as the rice blast disease. The critical problem in dealing with rice blast was not a lack of effort, but rather the lack of effective technologies. Preventative measures such as spraying fungicides could be taken, but this came at the environment's cost and risks to human health. Herein, we strived to create an alternative method, a scientific mechanism using synthetic biology that was effective and easy to access for farmers. We achieved this by combining synthetic biology with nanotechnology that helped visualize the detection using a clear color change. This visualization using color change would allow farmers to detect the presence of diseases without the interference of laboratories, speeding up the process to detect this disease as early as possible.
In principle, coupling synthetic biology with a nano detection system will allow for an innovative sensor development that is cheap and easy to use. To achieve this protocol, we employed a plasmonic DNAzyme point-of-care DNA detection. The successful DNAzyme detection of the mif23 gene of Magnaporthe oryzae showed an effective DNAzyme cleavage activity. After that, we sought to use the principle of nanotechnology. At the core, nanotechnology allows us to understand and control dimensions for better and more desirable technologies. By combining this nanotechnology with DNAzymes, we could conceive a simple and effective mechanism of use as follows:
Here farmers will be able to get harvested DNA from their rice crops, add it with functionalized gold nanoparticles and DNAzymes, and receive a color change if the target pathogenic gene is present in solution. In principle, the nano detection would function as illustrated here:
Two sets of gold nanoparticles (GNP-TS1 & GNP- TS2) were previously functionalized with thiol modified DNA strands T51: 3'-tgc cgg tca cgg cg ctg tc-5' and TS2: 3'-atc gtt ggg gtg acc gag c-5', respectively. These strands were designed as complementary sequences to our target gene strand TG: 5'-acg gc agt gec ggc gac agc tet agc aac cc act gg teg g-3'. Through hybridization, this in turn, cross-links GNP-TS1 and GNP-TS2 creating this square-like aggregate structure.
As such, the color changes from red to purple would act as a visual readout. This color-based visual readout would allow our system to be an appropriate point-of-care sensor using sound, less costly, or complex equipment. By developing this readily available detection point of care device for the rice blast disease, we hope to help our community and farmers worldwide prevent devastating crop loss. Moreso, given that our detection methods are not invasive to the surrounding ecosystem and pose no harm to humans who will eventually consume the crops, the use of nanoscience serves to substantiate a multidisciplinary collaboration towards achieving our goal.
- 1. Bhandari, Humnath. "Global rice production, consumption and trade: trends and future directions." Proceedings of the Korean Society of Crop Science Conference. The Korean Society of Crop Science, 2019.
- 2. Lu, Yi, and Juewen Liu. "Functional DNA nanotechnology: emerging applications of DNAzymes and aptamers." Current Opinion in Biotechnology 17.6 (2006): 580-588.
- 3. Zagorovsky, Kyryl, and Warren CW Chan. "A plasmonic DNAzyme strategy for point‐of‐care genetic detection of infectious pathogens." Angewandte Chemie International Edition 52.11 (2013): 3168-3171.
- 4. Hill, Haley D., and Chad A. Mirkin. "The bio-barcode assay for the detection of protein and nucleic acid targets using DTT-induced ligand exchange." Nature protocols 1.1 (2006): 324-336.
Yonsei_Korea is a convergent team of students based in Seoul, South Korea striving to create meaningful change utilizing synthtic biology in the iGEM 2021 Competition.