BRC-BIO: Model-driven discovery and characterization of the metabolism of pigment-producing microalgae at genome-scale

San Diego State University Foundation, San Diego CA

Investigators

Abstract

Photosynthetic organisms, including microalgae, can produce high-value pigments by consuming light and carbon dioxide, the most abundant greenhouse gas in the atmosphere. Microalgae have a complex and very active metabolism; they are responsible for approximately 20% of the total photosynthesis on earth. However, the lack of understanding of microalgal metabolism has limited the ability to use these organisms to their full potential to address environmental, food, and health challenges. This research project focuses on developing computational tools to understand the light metabolism of the marine microalga Dunaliella salina and the freshwater microalga Haematococcus lacustris. The genome sequences of these microalgae will be used to build two knowledgebases that will be converted into metabolic models to further understand and control the necessary metabolic requirements to promote accumulation of pigments, specifically carotenoids. By increasing the fundamental understanding of the biology of these microalgae, the research will enable new light-driven solutions to sustainability challenges. For this dual experimental and computational project, a diverse research team will be formed that includes graduate, undergraduate and K-12 researchers. Students will engage in learning, teaching, and training in computational biology, nurturing the next generation of computational biologists who will develop future tools for biosustainability and the bioeconomy. Systems biology approaches have resulted in genome-scale computational models that accurately represent the metabolism of microorganisms. When applied to photosynthetic microorganisms, metabolic models offer the potential to exploit natural metabolic robustness and diversity to develop biotechnological processes. Of special interest in microalgae-based biotechnology is the production of pigments. Microalgal species such as Dunaliella salina and Haematococcus lacustris contain extraordinary genetic capabilities to produce carotenoids for a wide range of biotechnological applications. In this project, two genome-scale metabolic models will be built, one for the halophilic microalga Dunaliella salina and another for the freshwater microalga Haematococcus lacustris. The models will serve as knowledgebases that allow the evaluation and prediction of carbon, nitrogen, and phosphorus pathways under different conditions (e.g., nutrient inputs, uptake capabilities of new metabolites, and different light sources). Available multi-omics data and genomic information will be used to validate the content of the metabolic models. These models will be applied to study microalgal pigment production under stress conditions, providing insights into innovative culture conditions to maximize productivity. Overall, this research will guide the development of new culture strategies to improve pigment production in these biotechnologically important organisms. This hybrid experimental and computational project will further the establishment of a research program in computational biology of microalgae at San Diego State University to develop robust light-driven bioprocesses for improved growth and pigment production. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.