Project Description

Team Name:

SUSTechOCEAN

Village:

Climate Crisis

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Team Members

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Project Description

• Climate warming is progressively issuing a severe warning to humanity through its multifaceted and immense threats.
• We plan to design an efficient algal-bacterial co-culture system, utilizing three engineered bacteria—Vibrio natriegens, Shewanella oneidensis MR-1, and Synechococcus PCC 7942—to sustainably and efficiently convert carbon dioxide into calcium carbonate, achieving carbon sequestration for millennia.
• The highlights of this system include leveraging the extracellular electron uptake (EEU) metabolic pathway of Shewanella oneidensis MR-1 and the experimental use of Vibrio natriegens for the synthesis of various complex calcium carbonate precipitation regulators (CCPR), such as CARPs.

1. We aim to integrate hardware with biological systems, utilizing solar panels to generate electricity and activate the electron uptake pathway (EEU) in Shewanella oneidensis MR-1. This will revert it to an ancient state, enabling it to use the reductive tricarboxylic acid (rTCA) cycle to sequester carbon dioxide and synthesize desired organic compounds, such as formate.
2. Vibrio natriegens can utilize formate as a carbon source or sucrose and efficiently produce carbonic anhydrase (CA), coral acid-rich proteins (CARPs), and the engineered protein Cabp-Chbd. These proteins will significantly impel the precipitation of calcium carbonate.
3. The sucrose synthesized by cyanobacteria serves as an additional carbon source for us, enabling the efficient metabolism of two other engineered bacteria.

• In summary, we will artificially construct an accelerated mineralization rate system, emulating coccolithophores, to achieve an autotrophic carbon sequestration system. This approach aims to fundamentally address the climate crisis.

Keywords: co-culture system, Calcium carbonate precipitation, EEU, CCPR.

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Inspirations

• 2022 DTU-Denmark
• 2019 ITESO Guadalajara
• 2020 Technion Israel
• 2020 Botchan Lab Tokyo
• 2020 St Andrews
• 2020 MIT

References

1. Li, Y., Luo, Q., Su, J., Dong, G., Cao, M., & Wang, Y. (2023). Metabolic regulation of Shewanella oneidensis for microbial electrosynthesis: From extracellular to intracellular. Metabolic Engineering, 80, 1–11. https://doi.org/10.1016/j.ymben.2023.08.004
2. Mass, T., Drake, J. L., Peters, E. C., Jiang, W., & Falkowski, P. G. (2014). Immunolocalization of skeletal matrix proteins in tissue and mineral of the coral Stylophora pistillata. Proceedings of the National Academy of Sciences - PNAS, 111(35), 12728–12733. https://doi.org/10.1073/pnas.1408621111
3. Watanabe, T., Suzuki, K., Oyanagi, W., Ohnishi, K., & Tanaka, H. (1990). Gene cloning of chitinase A1 from Bacillus circulans WL-12 revealed its evolutionary relationship to Serratia chitinase and to the type III homology units of fibronectin. Journal of Biological Chemistry, 265(26), 15659-15665. https://doi.org/10.1016/S0021-9258(18)55449-1
4. Sun, W., et al., Promoting Extracellular Electron Transfer of Shewanella oneidensis MR-1 by Optimizing the Periplasmic Cytochrome c Network. Front Microbiol, 2021. 12: p. 727709.
5. Hoffart, E., Grenz, S., Lange, J., Nitschel, R., Müller, F., Schwentner, A., Feith, A., Lenfers-Lücker, M., Takors, R., & Blombach, B. (2017). High substrate uptake rates empower Vibrio natriegens as production
6. Mass, T., Drake, J. L., Haramaty, L., Kim, J. D., Zelzion, E., Bhattacharya, D., & Falkowski, P. G. (2013). Cloning and Characterization of Four Novel Coral Acid-Rich Proteins that Precipitate Carbonates In Vitro. Current Biology, 23(12), 1126–1131. https://doi.org/10.1016/j.cub.2013.05.007
7. Nawarathna, T. H. K., Nakashima, K., Kawabe, T., Mwandira, W., Kurumisawa, K., & Kawasaki, S. (2021). Artificial Fusion Protein to Facilitate Calcium Carbonate Mineralization on Insoluble Polysaccharide for Efficient Biocementation. ACS Sustainable Chemistry & Engineering, 9(34), 11493–11502. https://doi.org/10.1021/acssuschemeng.1c03730
8. Zhang, S., Sun, J., Feng, D., Sun, H., Cui, J., Zeng, X., Wu, Y., Luan, G., & Lu, X. (2023). Unlocking the potentials of cyanobacterial photosynthesis for directly converting carbon dioxide into glucose. Nature Communications, 14(1), 3425–3425. https://doi.org/10.1038/s41467-023-39222-w