Introducing Climate Change and Ocean Acidification
The increasing levels of carbon dioxide have numerous detrimental effects on the environment. Firstly, by trapping heat causes increases in global temperatures. These temperatures then power more intense weather events and melt ice reserves. Secondly, the ocean absorbs some of the excess carbon dioxide, leading to increasing acidity. Specifically, humans have caused oceans to become 30% more acidic since the Industrial Revolution , damaging coral reefs and other marine habitats in the process.
Cyanobacteria are one of the only organisms that have a historical precedent for changing the entire world’s climate and atmospheric composition. When trying to solve our carbon dioxide problems today, it makes sense to look back on nature’s example. Therefore, for our project, we chose to genetically engineer a well-studied and moderately fast-growing strain of cyanobacteria, Synechococcus elongatus PCC 7942 (S. elongatus), for the purpose of carbon capture. Specifically, we will engineer our cyanobacteria to efficiently produce and secrete a sugar called sucrose, which can be used in industrial fermentation to produce certain plastics and ethanol biofuel. By using cyanobacteria-derived sucrose as opposed to corn-derived sucrose, food prices for developing nations are not driven up, and unsustainable amounts of fertilizers and fossil fuels are not required . By using cyanobacteria-derived sucrose over sugarcane-derived sucrose, deforestation and disruption of the natural ecosystems in the Amazon rainforest are reduced .
Photosynthetic cyanobacteria strains such as S. elongatus can produce sucrose more efficiently than both corn and sugarcane. Previously engineered S. elongatus has consumed carbon dioxide and secreted roughly 80% of that carbon intake as sucrose . Crops such as sugarcane only allocate 15% of their carbon as sucrose, and large amounts of land and fertilizer are required for their production . Because of the high efficiencies involved, sucrose production from cyanobacteria may be an effective method for carbon capture by converting carbon dioxide into sugars that can be used to make stable, high-value products such as bioplastics and biofuels.
Application of Novel Promoters
Lab Automation, Directed Evolution, and Open-Source Protocols
This year, our team had the honor of winning an Opentrons OT-2 robot that we used for lab automation. We programmed several protocols with the Opentrons, including InterLab protocols and well plate setups.
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