Team:NFLS/Engineering
Our team is working on the degradation of cellulose. The inspiration of this study comes from our daily life. As high school students, we are surrounded by papers such as test papers and textbooks. However, through investigation, we find that there is no good solution for waste paper and straw. So we looked at cellulose, which is a core component of these substances, in hopes of finding better treatments.
Before that we had a lot of literature reading, browsing the Jay d. Keasling’s paper[1], we know the extracellular hydrolysis of cellulose completely there are several key obstacles, in the technology of biomass and intracellular cellobiose assimilation is an alternative to biological engineering strategy. In our system, we figured out that the most effective way to degrade cellulose is to degrade cellulose to cellobiose and then to glucose. So we used genetically engineered bacteria to build a highly efficient way to break down cellulose into glucose. Endoglucanase is an enzyme that breaks down cellulose into oligosaccharides. It also works with exoglucanase, which breaks down oligosaccharides into fibrinosaccharides and then breaks down glucose under the action of glucosidase. So we performed some experiments on endoglucanase to obtain reliable data for subsequent analysis, including tests of protein glue, SDS-PAGE, and enzyme efficiency assay. In doing so, we discovered that the problem with the design of the device before was that it could only be expressed inside the cell, and it didn't work outside the cell.
In our design, we hope that the element can be expressed in cells, so the introduction of the engineering thinking, have a purpose for further design, on the basis of the original components, topped with a signal peptide of OmpA, added a middle linker would connect it together to form a new part BBa_K3513000, could perfectly solve the problem that the original cannot be expressed in cells, and make its application more widely, the applicable scope to expand, forming a new part we registered this year. But because the cause of the outbreak of corona virus we were unable to return to new experiments to validate our new component functionality, and in order to compensate for this, we established the mathematical model, and do a variety of enzymes and disaccharide in and out of the dynamical model of engineering bacteria cells, data import to establish mathematical model, through the experiment to verify the feasibility of the improvement measures, as one of the success of the project can be quantitative measure. The research process of the team will be presented on the official website in the form of web pages to describe and explain the principle and model of system work. The team members will complete the team wiki in the way of division of labor, including the project background, description, design, and so on. By recording, we provide complete and detailed experimental inspiration, ideas and procedures so that others can follow our steps to repeat our experiments step by step, and the registered components can also be used by the next IGEM team.
In a word, our team has formed an engineering cycle to think and solve the cellulose decomposition problem we met through engineering thinking.
References
[1] Parisutham, V., Chandran, S. P., Mukhopadhyay, A., Lee, S. K., & Keasling, J. D. (2017). Intracellular cellobiose metabolism and its applications in lignocellulose-based biorefineries. Bioresource technology, 239, 496-506.
