A Metabolic Lens on Phytoplankton Physiology

Phytoplankton are communities of diverse groups of prokaryotic and eukaryotic single-celled organisms responsible for nearly 50% of global primary production. The relative abundance of individual groups changes dynamically in response to environmental perturbations. Recent studies suggest that such changes are primarily driven by the distinct physiological responses employed by each group towards a particular perturbation. Although knowledge of some of these responses has come to light in recent years, many aspects of their metabolisms remain unknown. We attempt to address this gap by studying the metabolism of several phytoplankton groups using metabolomics. Firstly, we developed a method to enhance the analysis of untargeted metabolomics data. Secondly, we constructed two conceptual models describing how metabolism of the raphidophyte Heterosigma akashiwo responds to phosphorus and nitrogen stress. These conceptual models revealed several new stress response mechanisms not previously reported in other phytoplankton. Finally, we compared the metabolic changes of several distinct phytoplankton groups to uncover possible adaptation and acclimations that distinguish them. This analysis revealed several pathways and metabolites that represent the studied groups. The contributions of these pathways and metabolites towards physiology may support the ecological fitness of these organisms.

Name thesis:degree_name

Doctoral

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2021

Author dc:creator

• McLean, Craig

Advisor dc:contributor.advisor

• Kujawinski, Elizabeth B.

Statement dc:rights

• In Copyright - Educational Use Permitted
• Copyright retained by author(s)

Licence dc:rights.uri

• https://rightsstatements.org/page/InC-EDU/1.0/

Handle dc:identifier.uri

https://hdl.handle.net/1721.1/140034

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/140034