Effects of a CRISPR-Cas9 Knockout of the Urease Gene in Thalassiosira Pseudonana

Abstract

Ocean acidification is a global problem directly caused by rising CO2 levels. As the oceans continue to absorb atmospheric CO2, the pH of the oceans will continue to fall. Ocean pH has already dropped by 0.1 points in the past three centuries, and it is expected to fall a further 0.4 points by the year 2100. This will lead to irreversible damage to multicellular organisms such as corals, mollusks, and even unicellular organisms such as diatoms. Although methods to reduce human-produced CO2 have been studied extensively, methods to mitigate cellular production of CO2 have not. Developing strains of organisms that release less CO2 and sequester more carbon-based compounds could be a key to slowing down ocean acidification. CRISPR-Cas9 is a potent biotechnology tool that could develop such organisms through genetic modifications. In this work, the CRISPR-Cas9-induced knock-out of the urease gene in the marine diatom Thalassiosira pseudonana is proposed as a potential method to reduce cellular CO2 production. In addition to preliminary experimentation that has been conducted, a variety of future experiments to further understand the metabolic and environmental effects of this gene edit are also proposed.