Using nitrogen-fixing cyanobacteria to drive solar-powered conversion of atmospheric carbon dioxide and nitrogen into valuable N-rich products
Project Overview
Nitrogen is essential for life on earth. Today, most of our nitrogen need is met by chemical conversion of atmospheric nitrogen into readily usable forms, but such conversion comes at a massive environmental cost. An alternative approach is based on biological conversion of nitrogen at ambient temperature, a greener process restricted to only a few select groups of microbes. Of these, cyanobacteria are uniquely capable of driving the energetically expensive nitrogen fixation reaction solely with solar power while simultaneously capturing carbon, and thus reducing the carbon footprint.
The use of cyanobacteria requires significant fundamental research, including development of robust growth conditions and systems level understanding of the biology of these photosynthetic autotrophs. We are using two strains representing the two contrasting paradigms that cyanobacteria use to accommodate the mutually antagonistic processes of oxygenic photosynthesis and nitrogen fixation: temporal separation in a unicell (Cyanothece 51142) and spatial separation in a multicellular filament (Anabaena 33047).
We focus on the production of guanidine, ammonia and urea, three nitrogen rich compounds that can serve as substitutes for synthetic fertilizers. We are working to engineer novel enzymes capable of catalyzing the conversion of atmospheric nitrogen into these compounds, and membrane transporters that will secrete the products out of the cell. Multiomics studies and machine learning tools will unravel the fundamental principles underlying the regulation of carbon and nitrogen fixation in cyanobacteria and their channelization towards the products of interest. Our goal is to develop chassis strains that can produce sufficient quantities of fertilizer compounds for pilot scale-up geared towards commercialization of the concept.
Our research team of seven investigators from Washington University, National Renewable Energy Laboratory, and Alabama State University, brings together significant interdisciplinary expertise in cyanobacterial systems biology, metabolic modeling, machine learning and synthetic biology. An important mission of this project is to train students from diverse backgrounds, equipping a future workforce with modern biomanufacturing technologies.
Project Collaborators
Yinjie Tang
Washington University
Yixin Chen
Washington University
Jianping Yu
National Renewable Energy Laboratory (NREL)
Wei Xiong
National Renewable Energy Laboratory (NREL)
Harvey Hou
Alabama State University
2024 Cyanobacteria and Algae Research and Education (CARE) Workshop
https://sites.google.com/alasu.edu/care-2024/home
Vida Dennis
Alabama State University
Funding Information
This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research, under Award Number DE-SC0024702